DE3779601T2 - ACID CATALYSTS AND METHOD FOR USE. - Google Patents

Description

This invention relates to acid-catalyzed organic reactions and, more particularly, to methods for carrying out acid-catalyzed reactions of organic compounds that are accelerated by strong acids.

Description of the state of the art

The ability of sulfuric acid to catalyze a variety of organic reactions is well known. It is also known that urea (a chalcogen compound useful in this invention) and sulfuric acid combine to form adducts, including the monourea-sulfuric acid adduct and the diurea-sulfuric acid adduct. For example, DF du Toit, Verslag Akad. Wetenschappen, 22, 573-4 (summarized in Chemical Abstracts, 8, 2346, 1914) disclosed that urea forms certain compounds with oxalic acid, acetic acid, hydrochloric acid, nitric acid and sulfuric acid. LH Dalman, "Ternary Systems of Urea and Acid. I. Urea, Nitric Acid and Water. II. Urea, Sulfuric Acid and Water. III.Urea, Oxalic Acid and Water"; JACS, 56, 549-53 (1934), disclosed the phase relationships between the solid phase and saturated solutions containing urea and sulfuric acid at 10ºC and 25ºC. The Sulfur Institute, Sulfur Institute Bulletin No. 10 (1964) "Adding Plant Nutrient Sulfur to Fertilizer", disclosed that urea reacts with sulfuric acid to form two complexes of "urea sulfate" which are useful fertilizers. Processes for producing certain combinations of urea and sulfuric acid are disclosed by Verdegaal et al. in U.S. Patent 4,310,343 and by Jones in U.S. Patent 4,116,664.

A wide variety of organic transformations are catalyzed by the proton-donating ability of strong acids. Such reactions have been studied in detail and widely discussed in the literature. For example, the Kirk-Othmer Encyclopedia of Chemical Technology, 3rd edition, John Wiley and Sons, New York, 1980, discusses a variety of organic reactions catalyzed by strong acids, including mineral acids, transition metal halides such as Friedel-Crafts catalysts, conjugated Friedel-Crafts catalysts, and others. Kirk-Othmer defines acid-catalyzed reactions as those in which a proton is transferred from the catalyst to the reactant, which is thereby converted into an unstable state that immediately leads to the reaction under consideration (Volume 5, page 33). While the proton donation mechanism of acid-catalyzed reactions referred to in Kirk-Othmer may or may not be responsible for the reactions that occur in all acid-catalyzed reactions, strong acids are known to accelerate numerous reactions, including oxidative addition, reductive addition, esterification, transesterification, hydrogenation, isomerization (including racemization of optical isomers), hydrolysis and alcoholysis, alkylation, olefin polymerization, Friedel-Crafts reactions, demetallization of organic compounds, and nitration reactions, among others. Strong acids known to accelerate such acid-catalyzed organic reactions include sulfuric acid, nitric acid, hydrochloric acid, transition metal halides, including the so-called Friedel-Crafts catalysts, for example the halides of aluminum, gallium, boron, titanium, vanadium, tin, and others, and conjugated Friedel-Crafts catalysts, also known as Bronsted-Lewis superacid mixtures (Kirk-Othmer, Vol. 11, 295), such as mineral acid adducts of transition metal halides.

All known strong acid catalysts and the processes involving their use for accelerating acid-catalyzed organic reactions suffer from one or more disadvantages. For example, strong mineral acids accelerate side reactions that form undesirable byproducts, destroy the organic feedstock or product, and/or consume or deactivate the catalyst. Sulfuric acid is a strong sulfating, sulfonating, oxidizing, and dehydrating agent, and because of these activities, it is consumed in most organic reactions by side reactions involving these mechanisms. In addition, the sulfonating and oxidizing activities of sulfuric acid lead to the sulfonation and oxidation of the organic feedstocks and/or products. Similar shortcomings exist for the other strong mineral acids, such as hydrochloric acid and nitric acid. Hydrochloric acid chlorinates the reactants and thereby consumes the feedstock to produce undesirable chlorinated byproducts. Nitric acid oxidizes and/or nitrates organic compounds. Hydrofluoric acid fluorinates organic reactants and products. The transition metal halides, including the Friedel-Crafts catalysts, are difficult to handle because they must be isolated from water and reducing agents. Such catalysts also halogenate organic feedstocks and products.

Accordingly, there is a need for improved processes for conducting acid-catalyzed organic reactions and for improved acid catalysts for use in such reactions which accelerate the desired acid-catalyzed organic reaction but avoid the side reactions normally associated with acid-catalyzed organic reactions reduce or exclude.

It is therefore a primary object of this invention to provide novel processes for carrying out acid-catalyzed reactions of organic compounds in the presence of compositions comprising sulfuric acid.

Another task is to provide novel processes for the oxidative addition of organic compounds.

Yet another task is to provide novel processes for the reductive addition of organic compounds.

Another task is to provide novel processes for the esterification and transesterification of organic compounds.

Yet another object of this invention is to provide novel processes for hydrogenating organic compounds containing olefinic unsaturation.

Another task is to provide novel processes for the isomerization of organic compounds.

Yet another task is to provide novel processes for the hydrolysis, alcoholysis, thiolysis and amination of organic compounds.

Another task is to provide novel processes for the alkylation of organic compounds.

Yet another task is to provide novel processes for the polymerization of olefinic compounds.

Another task is to provide novel Friedel-Crafts-catalyzed organic reactions.

Yet another object of this invention is to provide novel methods for demetallizing organic compounds.

Another task is to provide novel processes for the nitration of organic compounds.

Other objects, aspects and advantages of this invention will become apparent to those skilled in the art in view of the following disclosure and the appended claims.

In one aspect, the invention thus consists in a process for carrying out the acid-catalyzed reaction, other than hydrolysis, of an organic compound, which reaction can be acid-catalyzed by sulfuric acid, which comprises the steps of: carrying out said reaction in the presence of a catalytically active amount of monoadduct of sulfuric acid and a chalcogen-containing compound having the empirical formula

R₁- -R₂

wherein X is a chalcogen, R₁ and R₂ are each independently selected from the group consisting of hydrogen, NR₃R₄ and NR₅, at least one of R₁ and R₂ is other than hydrogen, R₃ and R₄ are each independently selected from hydrogen and monovalent organic radicals, and R₅ is a divalent organic radical.

The invention further consists in a process for carrying out the acid-catalyzed reaction of an organic compound, which reaction can be acid-catalyzed by sulphuric acid, which comprises the steps of: carrying out said reaction in the presence of a catalytically active amount of the Monoadduct of sulphuric acid and a chalcogen-containing compound other than urea, with the empirical formula

R₁- -R₂

wherein X is a chalcogen, R₁ and R₂ are each independently selected from the group consisting of hydrogen, NR₃R₄ and NR₅, at least one of R₁ and R₂ is other than hydrogen, R₃ and R₄ are each independently selected from hydrogen and monovalent organic radicals, and R₅ is a divalent organic radical.

The novel processes of this invention involve acid-catalyzed reactions of one or more organic compounds in the presence of the described catalysts. The solvent- and/or surfactant-containing catalysts are particularly useful for many acid-catalyzed organic reactions, especially those involving the more lipophilic, i.e., hydrophobic materials. Surfactants and solvents have been found to enhance the activity of the chalcogen/acid component toward more lipophilic substrates. Likewise, the novel conjugated acid catalysts can be used in the novel processes of this invention.

In particular, the novel processes of this invention relate to the conversion of organic materials, at least in part, by the acid-catalyzed activity of sulfuric acid. Thus, they include all acid-catalyzed organic reactions that are catalyzed by sulfuric acid, such as

(a) oxidation of one or more organic compounds in the presence of an oxidising agent;

(b) Reduction of one or more organic compounds by Reaction with a reducing agent such as hydrogen;

(c) hydrolysis of one or more organic compounds by reaction with water and/or one or more alcohols and/or thiols;

(d) oxidative addition of one or more organic compounds by reaction with an oxidising agent;

(e) reductive addition of organic compounds by reaction with a reducing agent;

(f) esterification of amides, nitriles, carboxylic acids, acyl halides, thiocarboxylic acids and/or carboxylic anhydrides by reaction with alcohols and/or thiols;

(g) hydrogenation of organic compounds containing carbon/carbon unsaturation by reaction with hydrogen;

(h) alkylating organic compounds by reaction with an organic alkylating agent having at least one olefinic carbon/carbon bond;

(i) polymerising organic compounds containing olefinic unsaturation in the presence of an oxidising agent;

(j) Friedel-Crafts reactions of organic compounds with hydrocarbon halides;

(k) isomerization of hydrocarbons having from 4 to about 20 carbon atoms per molecule;

(l) demetallization of organometallic compounds by reaction with water and/or alcohols; and

(m) Nitration of organic compounds by reaction with a nitrating agent such as nitrogen(II) oxide.

The processes of this invention eliminate most, if not all, of the deficiencies associated with acid-catalyzed conversion of organic compounds in the presence of sulfuric acid. The chalcogen compound/sulfuric acid components minimize or completely eliminate the undesirable oxidation, dehydrogenation and sulfonation activity of sulfuric acid, yet retain the strong proton-donating ability of the acid. Thus, the sulfuric acid contained in the chalcogen compound/acid component is not destroyed during acid-catalyzed organic reactions due to sulfonation, oxidation or other reactions associated with sulfuric acid. At the same time, organic feedstocks are not destroyed or converted to undesirable byproducts by side reactions commonly associated with sulfuric acid. All of these advantages exist in all forms of chalcogen compound/sulfuric acid components used in the processes of this invention, including the novel surfactant-containing catalysts and the novel conjugated transition metal halide catalysts. In addition, the solvent- and surfactant-containing catalysts exhibit improved catalytic activity for the conversion of organic compounds according to the processes of this invention, particularly for the conversion of more lipophilic compounds and organic materials containing lipophilic material, such as fats, waxes, and higher molecular weight organic substances.

Without wishing to be bound to a particular theory, it is currently believed that the adduct formation of sulphuric acid with compounds such as the chalcogen compounds described, which are able to donate electrons to the sulphuric acid, increases the lability of the acid hydrogens in in a manner that inhibits the tendency of the acid to undergo undesirable side reactions. Stronger electron donors are thought to inhibit the lability of acid hydrogen to a greater extent than does the addition of two rather than one chalcogen molecules to each acid molecule. For example, the monourea adduct of sulfuric acid is a selective, active acid catalyst, while the diurea adduct is essentially inactive as an acid catalyst.

DETAILED DESCRIPTION OF THE INVENTION

This invention provides novel processes for carrying out acid-catalyzed organic reactions, particularly organic reactions known to be catalyzed by sulfuric acid.

The chalcogen compound/sulfuric acid components useful in the processes of this invention contain a combination of sulfuric acid and one or more specific chalcogen compounds in which the molar ratio of the chalcogen compound to sulfuric acid is less than 2. In this range of molar ratios, at least a portion of the sulfuric acid is present as a mono-adduct of the sulfuric acid. In one embodiment, the chalcogen compound/acid component may optionally contain a surfactant, solvent, or other components. Surfactants and solvents increase the activity of the acid component toward organic materials, particularly toward materials containing lipophilic components such as fats, oils, waxes, and the like. The chalcogen compound/sulfuric acid component, with or without a surfactant, may also be combined with one or more organic or inorganic reactants that participate in the desired organic reaction to form a composition useful in carrying out the desired organic reaction. In another embodiment, the chalcogen/acid Component, with or without surfactants, can be combined with a conventional transition metal halide catalyst to form a conjugated Friedel-Crafts catalyst useful in this process.

The processes of this invention involve the acid-catalyzed conversion of organic compounds. In particular, these processes can be used for the acid-catalyzed conversion of any organic material that can be converted by sulfuric acid catalysis, and usually without the occurrence of undesirable side reactions normally associated with sulfuric acid. Illustrative of suitable acid-catalyzed reactions are oxidation, especially oxidative addition; esterification; transesterification; hydrogenation; isomerization, including racemization of optical isomers; hydrolysis and alcoholysis by reaction with water, alcohols or thiols; alkylation; olefin polymerization, Friedel-Crafts reactions; demetallization and nitration. According to these processes, the organic reactant(s) is/are contacted with the chalcogen compound/sulfuric acid component in the form of a solution in water or other solvents or as a molten mixture of chalcogen compound and sulfuric acid.

The chalcogen compound/sulfuric acid components are reaction products of sulfuric acid and one or more specific chalcogen-containing compounds in which the molar ratio of chalcogen compound to sulfuric acid is less than 2. In such components, at least a portion of the sulfuric acid is present as a mono-adduct of sulfuric acid and the chalcogen compound. These components can be used in the processes disclosed herein as melts, as solutions of such mixtures in water or other solvents, or as solids in which the chalcogen compound/sulfuric acid component is encapsulated in a solid support, such as carbon. refractory oxides such as silica, alumina and the like, acidic or basic ion exchange resins or zeolites such as the natural and synthetic aluminosilicates, and combinations of such supports. The catalysts may also contain optional components such as surfactants and transition metal halides. Other components which do not substantially negate the proton donating activity of the mono-adduct of sulfuric acid may also be present.

The applicable chalcogen-containing compounds have the empirical formula

R₁- -R₂

wherein X is a chalcogen, R₁ and R₂ are independently selected from hydrogen, NR₃R₄ or NR₅, wherein at least one of R₁ and R₂ is other than hydrogen, R₃ and R₄ are independently selected from hydrogen and a monovalent organic radical, and R₅ is a divalent organic radical. One of the monovalent radicals R₃ and R₄ may be hydrogen and one or both of R₃ and R₄ may be may be any organic radical including alkyl, aryl, alkenyl, alkenylaryl, aralkyl, aralkenyl, cycloalkyl, cycloalkenyl or alkynyl which may be unsubstituted or substituted with pendant functional groups such as hydroxyl, carboxyl, oxide, thio, thiol or others, and may contain acyclic or cyclic heteroatoms such as oxygen, sulfur, nitrogen or others. R₅ may be any divalent organic radical such as alkdyl, ardyl, alkendyl, alkindyl, aralkdyl, aralkindyl which may contain pendant atoms or substituents and/or acyclic or cyclic heteroatoms as described for R₃ and R₄. Preferably both R₁ and R₂ are other than hydrogen, both R₃ and R₄ are selected from hydrogen and hydrocarbon radicals which in combination contain about 10 carbon atoms or less, and X is preferably oxygen or sulfur, most preferably oxygen. Such substituents are presently preferred due to their relatively higher chemical stability. Particularly preferred chalcogen-containing compounds are urea, thiourea, formamide, and combinations of these.

The chalcogens are elements of periodic group VI-B and include oxygen, sulfur, selenium, tellurium and polonium. Oxygen and sulfur are currently preferred due to low cost, availability, low toxicity and chemical activity, and oxygen is the most preferred.

The chalcogen compound/sulfuric acid components may contain unreacted (free) sulfuric acid or the diadduct of sulfuric acid. Useful and preferred ratios of chalcogen compound, sulfuric acid, and the mono- and diadducts of sulfuric acid, relative to one another, may conveniently be expressed by the chalcogen compound/sulfuric acid molar ratio. This ratio will be less than 2, usually in the range of about 1/4 to about 7/4, preferably about 1/2 to about 3/2, and most preferably between about 1/1 and about 3/2. Molar ratios in the range of about 1/4 to about 7/4 define compositions in which at least 25% of the sulfuric acid is present as the monoadduct of sulfuric acid. Molar ratios in the range of 1/2 to about 3/4 define compositions in which at least 50% of the sulfuric acid is present as the monoadduct. The most preferred molar ratio range of about 1/1 to about 3/2 defines compositions containing substantially no uncomplexed sulfuric acid and in which at least 50% of the sulfuric acid is present as the monoadduct of sulfuric acid. The most preferred combinations have chalcogen compound/sulfuric acid molar ratios of about 1/1. In such combinations, substantially all of the sulfuric acid as the monoadduct of sulfuric acid, and such compositions are substantially free of uncomplexed sulfuric acid. Substantial amounts of uncomplexed sulfuric acid, that is, sulfuric acid that is not complexed with a chalcogen compound as either the mono- or diadduct, are less preferred because sulfuric acid, when present in substantial amounts, can accelerate side reactions such as oxidation, sulfonation, dehydration, and/or other reactions. Although the diadduct is generally not detrimental to the performance of the monoadduct components as acid catalysts for organic reactions, it has little or no proton donating ability and thus little or no activity as a catalyst for acid-catalyzed organic reactions.

Useful solutions contain a catalytically active amount of the monoadduct of sulfuric acid in a suitable solvent. Very low monoadduct concentrations, e.g., on the order of about 0.5% by weight of the solution (or melt), are sufficient to promote a variety of acid-catalyzed organic reactions. However, higher concentrations of the monoadduct are generally preferred. The solutions will thus usually contain at least 0.5, generally at least about 1, preferably at least about 5, and most preferably at least about 10% by weight of chalcogen compound and sulfuric acid, based on the combined weight of these two components. Higher concentrations of chalcogen compound and sulfuric acid provide increased catalytic activity. For example, solutions containing at least 50% and even 85% or more by weight of the combination of chalcogen compound and sulfuric acid, in combination, will comprise from 0.5 to about 90, usually from about 1 to about 90, and preferably from about 5 to about 90% by weight of the solution.

Each solution for dissolving the chalcogen compound/sulphuric acid A solvent suitable for the urea/sulfuric acid component under the reaction conditions may be used. Suitable solvents include polar solvents such as water, dimethyl sulfoxide (DMSO), halogenated hydrocarbons such as trichloromethane, oxidized hydrocarbons such as methyl ethyl ketone and tetrahydrofuran, and the like. The solvent is preferably non-reactive with the chalcogen compound/sulfuric acid component, the organic feedstocks, intermediates or products, or other components used in the acid-catalyzed organic reactions, unless, of course, the organic feedstock is also used as the solvent for the urea/sulfuric acid component.

When water is used as the sole solvent or as a component of the solvent, I have observed that, at relatively high water concentrations, water begins to displace the chalcogen compound as an adduct on the sulfuric acid, thus releasing free sulfuric acid into the system. This process is reversible, i.e., when water is removed from the system, the chalcogen compound/sulfuric acid adduct reforms. For these reasons, the presently preferred compositions and catalyst systems have H₂O/(chalcogen compound + H₂SO₄) molar ratios of about 5 or less, most preferably about 2.5 or less.

Melts of the compositions containing chalcogen compound/sulfuric acid components having melting points above room temperature, e.g., about 21°C (70°F), can also be used to catalyze the acid-catalyzed organic reactions. The active components useful in this embodiment are solids at room temperature and are converted to melts by heating to elevated reaction temperatures. In this embodiment, the melts are typically at least about 50 and preferably at least about 80 weight percent of the chalcogen compound/sulfuric acid component, based on the combined weight of chalcogen compounds in sulfuric acid. The melts will usually contain at least about 20, generally about 50, preferably at least about 80 weight percent of the preferred monoadduct of sulfuric acid.

The compositions used in the methods of this invention may also contain one or more surfactants which are preferably, although not necessarily, chemically stable in the presence of the acidic adduct component and in the presence of other components used in the methods of this invention for a significant period of time. Surfactants increase the activity of the acidic adduct toward substantially all non-polar organic compounds, including lipophilic organic materials such as waxes, proteins, ligands, fats, alkanes, higher molecular weight acids, alcohols, and the like. For example, surfactants increase the activity of the liquid acidic adduct composition toward cellulosic material such as growing or harvested vegetation coated with or containing a significant amount of waxy cuticle. Surfactants thus increase the acid-catalyzed hydrolysis of lipid-containing cellulosic material and increase the herbicidal activity of the urea/sulfuric acid component against growing vegetation, as discussed below and in pending European patent applications 86 105 942.6, 86 111 365.2 and 87 300 147.3. The herbicidal activity of the described chalcogen compound/sulfuric acid components is apparently based, at least in part, on their ability to catalyze the chemical conversion of cellulose and other organic compounds in the plant material. As described here, these chalcogen compound/sulfuric acid components are also capable of catalyzing reactions involving organic compounds other than plant material.

The selected surfactant is preferably sufficiently chemically stable in the liquid or solid compositions or in the melts formed from the solid compositions to ensure that the surfactant retains sufficient wettability to the organic material for a period of time required for the manufacture, storage, transportation and use of the chalcogen compound/sulfuric acid component. The stability of any surfactant can be readily determined by adding an amount of the surfactant to the chalcogen compound/sulfuric acid composition in which it is to be used and monitoring the combination by conventional analytical techniques based on nuclear magnetic resonance (NMR). NMR can be used to monitor the frequency and height of spectral peaks characteristic of a selected nucleus, e.g. a hydrogen nucleus in the surfactant. Persistent spectral peak height and frequency over a period of 5 to 6 hours indicates stability. Decreased peak height or a shift in peak frequency associated with the selected nucleus indicates instability, i.e. the arrangement of the functional groups in the surfactant molecule has been modified.

Illustrative of classes of stable surfactants are nonionics, such as the alkylphenol polyethylene oxides, anionics, such as the long chain alkyl sulfates, and cationics, such as 1-hydroxyethyl-2-heptadecenylgloxalidine. Of these, the nonionic polyethylene oxide surfactants are particularly preferred. Illustrative of preferred specific surfactants is the nonionic surfactant marketed under the trademark T-MULZ 891 by Thompson-Hayward, Inc.

The surfactant concentration is preferably sufficient to increase the wetting ability of the chalcogen compound/acid component for the organic material to be converted. Even very low surfactant concentrations increase the wettability of the acid adduct component to some extent. The surfactant concentration will usually be at least about 0.05, generally at least about 0.1, and preferably at least about 0.2% by weight of the solution used in the process of this invention. Surfactant concentrations of from about 0.2 to about 1% by weight are adequate for most applications.

The chalcogen compound/sulfuric acid component can be combined with transition metal halides to form the conjugate acid of the acid adduct with the transition metal halide. Such conjugate acids of transition metal halides, such as Friedel-Crafts catalysts and the transition metal halides used in the so-called Ziegler catalysts, are discussed in the Kirk-Othmer publication referred to above and in US-A-4,078,832; US-A-3,987,123; US-A-4,086,062 and US-A-4,008,360. For example, Kirk-Othmer, on page 856 of volume 12, describes the complex of hydrochloric acid with aluminum trichloride. The transition metal halide component of the conjugated acidic Friedel-Crafts catalysts of this invention can comprise halides of any transition metal, particularly the halides of aluminum, vanadium, boron, titanium, tin, gallium, and combinations thereof. The halide component can be selected from chloride, bromide, fluoride, and iodide, although the iodides are less active for accelerating acid-catalyzed organic reactions and are thus less preferred. The conjugated Friedel-Crafts catalysts of this invention can contain equimolar amounts of the monoadduct of sulfuric acid plus the transition metal halide, or they can comprise an excess of either of these two components. However, it is presently preferred that the conjugate acid contain from about 0.1 to about 2 moles of transition metal halide for each mole of mono-chalcogen compound/sulfuric acid adduct.

The useful chalcogen compound/sulfuric acid components can be prepared by reacting the chalcogen compound with sulfuric acid according to the methods described in US-A-4,445,925. This patent describes in part the preparation of urea/sulfuric acid components which are free of decomposition products of urea, sulfuric acid and the mono- or di-urea/sulfuric acid adducts and which are particularly preferred for preparing the chalcogen compound/sulfuric acid components of this invention. As described in US-A-4,445,925, the reaction of urea and sulfuric acid is extremely exothermic and, if not adequately controlled, can result in decomposition of the reactants or products and the formation of decomposition products such as amidosulfuric acid, ammonium sulfamate, ammonium sulfate and other materials. Reactions of sulfuric acid with other chalcogen compounds useful in this invention are also exothermic and similar precautions should be observed, particularly in preparing more concentrated solutions and melts. The formation of such decomposition products and the presence of such decomposition products in the compositions and processes of this invention is not preferred for several reasons. Such decomposition products can interfere with the acid-catalyzed conversion of organic compounds and can result in impurities in the final product. Decomposition also results in the loss of sulfuric acid which must be available to combine with the useful chalcogen compounds to form the active monoadduct of sulfuric acid.

Solid chalcogen compound/sulfuric acid components useful in preparing the melts and solutions of this invention can be obtained by crystallization from their corresponding aqueous solutions as described for urea/sulfuric acid components in pending European Application 86 105 942.6. The surfactant, if present, is either at approximately the same temperature as the chalcogen compound/sulfuric acid component or is entrained by the crystallized sulfuric acid adduct. Alternatively, if desired, the surfactant may be added to the dry or wet crystallized chalcogen compound/sulfuric acid component by any suitable mixing technique.

As described in said copending application 86,105,942.6, the aqueous solution of urea/sulfuric acid, designated therein as 18-0-0-17, has a crystallization temperature of 10°C (50°F). Designations such as 18-0-0-17 are commonly used in the agricultural industry to define the weight percentages of nitrogen, phosphorus, potassium and a fourth component, in this case sulfur, contained in a composition. Thus, 18-0-0-17 contains 18% nitrogen as urea, 0% phosphorus, 0% potassium and 17% sulfur by weight. The 18-0-0-17 solution has a urea/sulfuric acid molar ratio of about 1.2 and contains about 90% by weight of a combination of urea and sulfuric acid. Urea and sulfuric acid in combination comprise 80% by weight of the aqueous solution designated 10-0-0-19, which composition has a urea/sulfuric acid molar ratio of 0.6 and crystallizes at about 6°C (42°F). The aqueous solution designated 9-0-0-25 comprises approximately 96% by weight of a combination of urea and sulfuric acid, has a urea/sulfuric acid molar ratio of about 0.4 and crystallizes at -10°C (14°F). The reported crystallization temperatures of the three aqueous solutions of urea/sulfuric acid referred to above and the crystallization temperatures for other formulations of urea and sulfuric acid useful in the compositions and methods of this invention are illustrated in part by the isotherms in the ternary phase diagram for urea, sulfuric acid and water in the drawing, which is part of said pending application 86 105 942.6. Crystallization temperatures for other urea/sulfuric acid combinations and for combinations of sulfuric acid and other chalcogen compounds useful in the compositions and processes of this invention can be determined from this drawing or by cooling the selected solution until crystallization occurs. The crystallized material can be separated from the supernatant aqueous phase by any suitable solid/liquid separation technique such as filtration, centrifugation, decantation and the like and the recovered wet solid can be dried by evaporation if desired.

Since lower crystallization temperatures are required to separate the desired chalcogen compound/sulfuric acid component from the more dilute solutions, it is preferred to start with more concentrated solutions with higher crystallization points, such as the 18-0-0-17 urea/sulfuric acid composition, which contains only about 10% water. More concentrated solutions and those with higher crystallization temperatures, e.g., 25°C (77°F), are even more preferred since less cooling is required to obtain an equal amount of the chalcogen compound/sulfuric acid component. Essentially anhydrous solid compositions can be obtained by washing the dried, crystallized chalcogen compound/sulfuric acid component with a highly hydrophilic solvent, such as absolute ethanol or acetone. From 10 to 100 parts by weight of solvent per part by weight of solute is usually adequate for this purpose. Methods for preparing substantially anhydrous urea/sulfuric acid components containing about 1% by weight of water or less and which are more thermally stable than more water-containing compositions are discussed in said application 86 105 942.6. Such methods can be used to prepare other thermally stable, anhydrous chalcogen compound/sulfuric acid components useful herein.

The anhydrous monoadduct-containing components are stable at ambient conditions and have negligible vapor pressure up to their decomposition temperatures of up to 150ºC (300ºF). However, they decompose explosively at much lower temperatures in the presence of water. For example, the hydrous urea/sulfuric acid compositions decompose at 80ºC (176ºF).

The most preferred solid urea composition consisting of the 1/1 molar urea/sulfuric acid adduct has a melting point of about 38°C (100°F), and the melting point of the urea/sulfuric acid component indicates when the urea/acid ratio deviates from 1:1 in any direction in a manner parallel to the isotherms illustrated in the drawing of said application 86 105 942.6.

Liquid chalcogen compound/sulfuric acid compositions used in the methods of this invention can be prepared by any method capable of producing a solution of the desired composition. Thus, the surfactant and/or other components, when employed, can be added to the concentrated chalcogen compound/sulfuric acid solution during or immediately after its preparation by the method described in US-A-4,445,925, or such components can be added to the chalcogen compound/sulfuric acid solution prior to its use in catalyzing organic reactions according to the methods of the invention. Alternatively, the optional components, when employed, can be mixed with the selected solvent prior to or simultaneously with the solid or concentrated chalcogen compound/sulfuric acid component. Of course, the dissolution of the solid chalcogen compound/sulfuric acid compositions described above, containing the desired optional components in the selected solvent also result in the formation of the active liquid composition of this invention. The melts employed in several embodiments of this invention can be prepared simply by melting the selected solid composition either before or during contact with the organic material to be converted as described below.

The conjugated Friedel-Crafts acids of this invention can be prepared by reacting the chalcogen compound/sulfuric acid component with one or more transition metal halides. The reaction can be carried out by dissolving the chalcogen compound/sulfuric acid component in a polar solvent such as that described above and dissolving or dispersing the transition metal halide in the resulting solution. Agitation and elevated temperatures, such as temperatures in the range of about 32 to about 66°C (about 90 to 150°F), increase the rate of formation of the conjugated acid, i.e., the combination of the monoadduct and the transition metal halide.

The reactant-containing compositions of this invention can be prepared by mixing one or more organic and/or inorganic reactants, such as those discussed below, with one or more of the chalcogen compound/sulfuric acid components useful in the processes of this invention, including the conjugated Friedel-Crafts catalysts of this invention, in the presence or absence of an added solvent or surfactant. These compositions can be either homogeneous solutions or heterogeneous mixtures, including liquid-liquid, solid-liquid, or vapor-liquid mixtures of the chalcogen/sulfuric acid and/or conjugated acid components and one or more liquid, solid, or vapor reactants.

The novel processes of this invention involve acid-catalyzed reactions of organic compounds in the presence of a catalytically active amount of the described chalcogen compound/sulfuric acid components in the presence or absence of additional components such as surfactants, transition metal halides and/or the conjugated Friedel-Crafts catalysts of this invention, and reference to the chalcogen compound/sulfuric acid components in the description of the processes of this invention is meant to include compositions containing such additional components. The novel solvent and/or surfactant-containing compositions are preferred in reactions involving relatively lipophilic organic materials since surfactants enhance the activity of the chalcogen compound/sulfuric acid component toward such materials.

Any organic reaction catalyzed by relatively strong acids, such as sulfuric acid, can be carried out by the methods of this invention. A variety of such reactions are well known in the literature, and many are discussed in the Kirk-Othmer publication Encyclopedia of Chemical Technology referenced above and in the references referenced therein, the disclosures of which are incorporated herein by reference in their entirety. Illustrative of such acid-catalyzed reactions are (1) oxidation, such as oxidative addition reaction; (2) reduction, such as reductive addition reaction; (3) esterification; (4) transesterification; (5) hydrogenation; (6) isomerization, including racemization of optical isomers; (7) hydrolysis, which for the purposes of this disclosure includes alcoholysis and thiolysis, i.e., the reaction of organic compounds with alcohols and thiols; (8) alkylation; (9) polymerization of olefinically unsaturated organic compounds; (10) Friedel-Crafts reactions; (11) demetallation; and (12) nitration reactions. Other reactions known to be catalyzed by acid catalysts can also be catalyzed by the chalcogen compound/sulfuric acid components described herein. The specific processes discussed further can be catalyzed by any of the chalcogen compound/sulfuric acid catalyst components discussed above, including the surfactant and/or transition metal halide containing components.

Acid-catalyzed oxidative reactions primarily involve the abstraction of hydrogen from an organic compound by reacting the compound with an oxidizing agent. An illustrative example of such reactions is the oxidative addition of organic compounds, illustrated by the following equation:

R₁H + R₂H + 1/2 O₂ --> R1R2 + H₂O (1)

wherein R₁ and R₂ are identical or different hydrocarbon radicals, including straight-chain and branched-chain alkanes; alkenes; alkynes; aromatics; alkyl-, alkenyl- and alkynyl-substituted aryls; and aryl-substituted alkanes, alkenes and alkynes, of essentially any molecular weight, but usually having from 1 to about 40 carbon atoms per molecule. Preferred reactants include olefins, particularly alpha-olefins.

The acid-catalyzed oxidation reactions can be accelerated by contacting the organic compound to be converted with the catalyst component in the presence of an oxidizing agent, which is preferably oxygen, as illustrated in the above equation. The oxidative The addition reaction illustrated in the equation requires only that the organic compound contain a carbon/hydrogen bond capable of undergoing oxidative addition reactions. The organic compound may be dispersed or dissolved in either a melt or a solution of the catalyst component in a suitable solvent, or it may be brought into contact with the catalyst component by conventional mixing and contacting techniques.

Acid-catalyzed reduction reactions of organic compounds according to the methods of this invention can involve the addition of hydrogen to unsaturated organic compounds. Illustrative reactions include the hydrogenation of organic compounds containing olefinic, alkynylic or aromatic unsaturation and reductive addition reactions such as dimerization, oligomerization and polymerization reactions as schematically illustrated in the following equation: and higher polymers (2)

wherein R₁, R₂, R₃ and R₄ are identical or different functional groups selected from hydrogen and alkyl moieties having from 1 to about 20 carbon atoms. Preferred reactants include normal and branched chain alkenes and alkenyl aromatic compounds. The acid-catalyzed reduction reactions can be carried out by contacting the organic compound to be converted with a reducing agent such as hydrogen, hydrazine and/or other reducing agents in the absence of oxidizing agents.

Such reactions can be carried out by preparing a composition, such as a melt, solution or dispersion, containing the unsaturated organic compounds, the reducing agent and the chalcogen compound/sulfuric acid component in the absence of oxidizing agents under conditions of temperature and pressure sufficient to accelerate the reductive addition reaction. As illustrated by the example discussed below, the reductive addition of propylene can be accelerated at room temperature.

Acid-catalyzed esterification reactions according to the methods of this invention typically involve reacting an esterifiable organic compound having one or more amide, nitrile, carboxylic acid, carboxylic anhydride, acyl halide and/or thiocarboxylic acid groups with an organic alcohol or thiol in the presence of the acidic catalyst component. Such reactions can be carried out by contacting a composition containing the chalcogen compound/sulfuric acid catalyst component, one or more esterifiable organic compounds and one or more alcohols, thiols and/or amines under esterification conditions. Reactions of acids, amides and thioacids are illustrated by the following equation:

R₁(-Y)xHx + R₂(Z)xHx T R₁(-Z)xR₂ + H2xYx (3)

in which R₁ and R₂ are any organic radicals including natural and synthetic polymers such as partially hydrolyzed protein or cellulose, nylon, dacron, etc., and Y and Z are identical or different divalent radicals selected from oxygen, sulfur and NH groups. x is an integer of 1 or greater and may range up to 1000 or more depending on the molecular weight of the compound involved. For example, partially hydrolyzed polymers such as those referred to above may contain 100 or more functional groups capable of undergoing esterification by the acid-catalyzed processes of this invention.

The reactions of alcohols, thiols and amines with organic cyanides and acyl halides, although not illustrated in equation (3) above, are well known and can be accelerated by the processes of this invention. For example, the reaction of alcohols with acyl chlorides can be catalyzed by the process of the invention to form the corresponding ester and hydrogen chloride, and the reactions of organic cyanides with water and/or alcohols result in the formation of the corresponding esters and ammonia, as discussed in Kirk-Othmer, Vol. 9, p. 302. The evolution of ammonia by esterification of nitriles and amides can result in consumption of a portion of the sulfuric acid in the catalyst component, but will not prevent the acid-catalyzed esterification from occurring. Sulfuric acid consumed by ammonia or other bases produced or present in esterification reactions (or in other acid-catalyzed reactions encompassed by the processes of this invention) can be replaced by adding additional sulfuric acid, if desired, during the process.

Although equation (3) above indicates that all acyl moieties are linked to an organic moiety identified as R₁, and that all alcohol, thiol and/or amine moieties are linked to an organic moiety identified as R₂, this form of equation is used only by way of example. For example, a polyfunctional carboxylic acid can be linked to a series of monofunctional alcohols; conversely, a series of monofunctional carboxylic acids, thioacids, etc., can be esterified by fewer molecules of a polyfunctional alcohol, thiol, etc.

Essentially any transesterification reaction can be carried out by the processes of this invention, including (a) ester/ester exchange, (b) alcoholysis involving the exchange of alcohol, thiol or amino groups, and (c) acidolysis involving the exchange of carboxylic acid, thiocarboxylic acid and/or amide groups. Such transesterification reactions can be carried out by contacting under esterification conditions a composition containing (1) the chalcogen compound/sulfuric acid component useful in this invention, (2) a carboxylic acid ester, thioester and/or amidoester, and (3) either (a) a different organoester, thioester and/or amidoester, (b) a carboxylic acid, thioacid or amide, (c) an alcohol, thiol and/or amine, or (d) combinations of (a), (b) and (c). Such reactions are schematically illustrated by the following equations:

(a) Ester-ester exchange

(b) Alcoholysis

R₁( -ZR₂)x + xR₃YH --> R₁( -YR₃)x + xR₂Z (4)

(c) Acidolysis

As in the case of the esterification illustrated by equation (3) above, the R1, R2, R3 and R4 moieties contained in equations 4(a), (b) and (c) may be identical or different organic moieties of substantially any molecular weight, Y and Z may be identical or different divalent radicals selected from oxygen, sulfur and NH groups, and x may represent any integer of 1 or greater. Also, as in the case of esterification, compounds containing one or more ester groups may be reacted with either mono- or polyfunctional esters, alcohols, thiols, acids, thioacids, etc. For example, alcohols, such as 1-butanol, can be reacted either with simple esters, such as ethyl acetate, to produce butyl acetate, or with complex polyamides, such as proteins, to produce the corresponding butyl esters of the amino acid contained in the protein.

The acid-catalyzed hydrogenation reactions of this invention can be carried out by contacting a composition containing (1) an organic compound containing carbon/carbon unsaturation, (2) hydrogen, and (3) the chalcogen compound/sulfuric acid-containing catalyst under hydrogenation conditions. The reaction can be carried out by subjecting a composition containing the acidic catalyst component, hydrogen, and an unsaturated organic compound to temperature and pressure conditions sufficient to promote hydrogenation. The hydrogenation of olefins is illustrated by equation (5):

R₁(CH=CH)xR2 + xH₂ --> R₁(CH₂-CH₂)xR₂ (5)

in which R�1 and R₂ identical or different are hydrogen or organic moieties of substantially any molecular weight; and x is any integer of 1 or greater. For example, the processes of this invention can be used to hydrogenate ethylene as well as polymers having molecular weights of 100,000 or more, which polymers contain a plurality of olefin linkages. They can also be used to hydrogenate benzene, alkyl or alkenyl aromatics, alkynes, and other unsaturated organic compounds. Olefinically unsaturated organic compounds, particularly hydrocarbon compounds, having from 2 to about 40 carbon atoms are presently preferred. The hydrogenation reactions can be accelerated by hydrogen, hydrazine, or other hydrogenating agents, and are preferably carried out in the absence of oxidizing agents such as oxygen and other oxidizing agents.

The acid-catalyzed isomerization reactions involve the isomerization of any organic compounds having four or more carbon atoms by contacting such compounds with the useful acid catalyst component under isomerization conditions. Such isomerization reactions can be carried out by contacting a composition containing the acid catalyst component and one or more organic compounds under isomerization conditions. Essentially all organic compounds can be isomerized by the processes of this invention, including hydrocarbons and organic compounds containing elements other than carbon and hydrogen, such as oxygen, sulfur, phosphorus, nitrogen, and the like. The presence of functional groups in the organic compounds employed in acid-catalyzed isomerization reactions of this invention that are reactive in the presence of the acid catalyst component can, in addition to isomerization, lead to the occurrence of other reactions. Nevertheless, isomerization will also occur.

The isomerization reactions encompassed by the processes of this invention are particularly useful for the isomerization of low molecular weight hydrocarbons having from 4 to about 20 carbon atoms per molecule. They are also useful for the racemization of optical isomers, i.e., the conversion of right- or left-handed isomers into the corresponding racemic mixture.

The acid-catalyzed hydrolysis reactions include the reaction of water, alcohols, thiols or amines with (a) carboxylic acid amidoesters, including polyamides; (b) carboxylic acid esters and polyesters, such as proteins, i.e., polyamino acid esters; (c) thiocarboxylic acid esters and polyesters; (d) esters and thioethers, including polyoxyethers and thioethers, such as cellulose, rayon, starches and other polysaccharides; (e) di- and polyalkylamines, including polyamines; (f) organic compounds containing olefinic unsaturation; and (g) epoxides. Such hydrolysis reactions can be carried out by contacting a composition comprising (1) the chalcogen compound/sulfuric acid component, (2) an organic compound having one or more hydrolyzable functional groups such as amidoester, acid ester, thioester, ether, thioether, amino, olefinic and/or epoxy linkages, and (3) a hydrolyzing compound such as water, alcohols, thiols and/or amines under conditions of temperature and pressure sufficient to promote hydrolysis of the hydrolyzable functional group. Alternatively, the organic compound having a hydrolyzable functional group such as amidoester, acid ester, etc. can be contacted under hydrolyzing conditions with a composition comprising the chalcogen compound/sulfuric acid-containing acidic catalyst and a hydrolyzing compound.

Several of the hydrolysis reactions encompassed by this embodiment of the invention are also encompassed by the transesterification processes of this invention, which, as discussed above, involve alcoholysis. Such reactions include the reaction of alcohols, thiols and/or amines with (1) mono- or polycarboxylic acid esters or polyesters; (2) mono- or polyfunctional thiocarboxylic acid esters or polyesters; and (3) mono- or polycarboxylic acid amido esters or polyamido esters.

A particularly interesting aspect of the hydrolysis reactions which can be effected according to the processes of this invention is that they can be used for either the partial or complete hydrolysis of natural or synthetic polymers such as polysaccharides including cellulose, starches and the like, protein, rayon, nylon and others by contacting such materials with the acidic catalyst components of this invention which contain water. Such reactions proceed even at room temperature and, if allowed to proceed to completion, result in complete depolymerization, i.e., complete hydrolysis of the polymer. For example, cellulose can be completely converted to glucose and proteins can be completely converted to amino acids by this process. The partial hydrolysis of cellulose appears to be responsible for the dramatic herbicidal activity of the chalcogen compound/sulfuric acid components used in the processes of this invention, and the herbicidal activity of urea/sulfuric acid components is discussed in greater detail in pending application No. 86 105 942.6. The ability of surfactants to enhance the activity of the urea/sulfuric acid component and to increase the diversity of controlled vegetation is also discussed in said pending application. The other chalcogen compound/sulfuric acid components show similar herbicidal activity when combined with surfactants.

The hydrolysis reactions are illustrated in part by the following equations, which are intended only as schematic representations of several acid-catalyzed hydrolysis reactions encompassed by the processes of this invention:

Equation 6(a) represents the complete acid-catalyzed hydrolysis of amino acid esters, including polyamino acid esters, such as proteins, by reaction with a hydrolyzing agent. According to formula 6(a), R₁ can be any difunctional organic moiety, Y can be hydrogen or a monofunctional terminal organic moiety such as potassium or another metal ion, R₂ is hydrogen or any organic moiety including hydrocarbon radicals having from 1 to 20 carbon atoms per molecule, X is oxygen, sulfur, nitrogen, or a combination of these, and n is an integer of 1 or greater. From Formula 6(a), it can be seen that the reaction of protein - a poly-α-amino acid ester - with water results in the formation of the amino acid monomer units contained in the protein when allowed to run to completion. Formula 6(b) illustrates the hydrolysis of a diorganoamine by reaction with an organic thiol in which R₁, R₂, and R₃ can be any organic moiety.

Formula 6(c) illustrates the hydrolysis of an organic thioester by reaction with water to produce the corresponding carboxylic acid and thiol, in which R1 and R2 can be any organic moieties. As in the case of the other hydrolysis reactions encompassed by this embodiment of the invention, alcohols, thiols and/or amines can replace or be combined with the water depicted in Formula 6(c).

Formula 6(d) schematically illustrates the hydrolysis of an organic epoxide by the acid-catalyzed reaction of the epoxide with water, thiols, alcohols or amines in which R4 and R5 are monovalent moieties selected from hydrogen and any organic moiety, R6 is a monovalent organic moiety having at least one carbon atom, and X is selected from oxygen, sulfur and nitrogen. The hydrolysis of olefins, including polyfunctional olefins, with water, alcohols, thiols or amines can be schematically illustrated by the following equation:

in which R₁ and R₂ and R₃ are identical or different monovalent moieties selected from hydrogen and any organic moiety, and X is O, S and/or NH, and n is any integer of 1 or greater.

Alkylation reactions according to the processes of this invention include the reaction of any organic compound capable of being alkylated by acid-catalyzed reaction with an organic reactant containing olefinic unsaturation. These reactions can be effected by contacting the alkylatable organic compound with a composition containing the chalcogen compound/sulfuric acid-containing acid catalyst and an organic reactant containing olefinic unsaturation and are schematically illustrated by the following equation:

R1; + R₂-CH=CH-R₃ --> R₁-H-CH₂-R₃ (8th)

in which R₂ and R₃ are identical or different and are hydrogen or organic units, in particular alkyl groups having 1 to 10 carbon atoms, and R₁ is an alkylatable organic compound, in particular straight-chain or branched-chain alkanes, aromatics, alkylaromatics and/or arylalkanes having 4 to 20 carbon atoms per molecule.

Acid-catalyzed olefin polymerization reactions include the polymerization of at least one organic compound containing at least one carbon/carbon olefin bond capable of undergoing acid-catalyzed polymerization by reacting the organic compound or compounds with the sulfuric acid-containing catalyst of this invention in In this embodiment, the reaction system is preferably substantially free of oxidizing agents. Such polymerization reactions are schematically illustrated by the following equation

in which R₁ and R₂ are selected from hydrogen and monovalent organic moieties, particularly hydrocarbon radicals containing 1 to 10 carbon atoms, and n is the number of monomer units incorporated into the polymer. Copolymers of two or more olefinic unsaturated monomers can be prepared. Illustrative of such copolymers are styrene-butadiene, ethylene-propylene, methacrylic acid-ethyl acrylate-hydroxyethyl acrylate and ethylene-dicyclopentadiene copolymers or the like, including the so-called hydrocarbon resins derived from cracked petroleum distillates, turpentine fractions, coal tar fractions and certain olefinic monomers such as the hydrocarbon resins discussed in Kirk-Othmer Volume 12, pages 842-847 in the references cited therein.

The Friedel-Crafts reactions involve the reaction of organic compounds, particularly hydrocarbon compounds capable of undergoing acid-catalyzed Friedel-Crafts reactions, with hydrocarbon halides. Such reactions can be effected by contacting one or more organic compounds with a composition comprising the sulfuric acid-containing catalyst and a hydrocarbon halide. Such Friedel-Crafts reactions are schematically illustrated by the following equation:

R₁H + R₂X --> R₁R₂ + HX (10)

in which R₁ is a monovalent organic moiety capable of undergoing Friedel-Crafts reactions with hydrocarbon halides, R₂ is a monovalent hydrocarbon moiety, preferably an alkyl group having 1 to 20 carbon atoms, and X is a halogen, preferably chlorine, bromine or fluorine, most preferably chlorine.

The acid catalyst component used to catalyze the Friedel-Crafts reaction can comprise any of the chalcogen compound/sulfuric acid components described, although the acidic components containing a Friedel-Crafts halide catalyst, such as the novel conjugated Friedel-Crafts catalysts of this invention, are preferred.

The acid-catalyzed demetallization reactions include the demetallization of organometallic compounds capable of undergoing acid-catalyzed demetallization by reaction with water and/or alcohols, and can be effected by contacting a composition containing organometallic compounds, the described sulfuric acid-containing catalyst, and water and/or alcohols under conditions of time and temperature sufficient to achieve the desired level of demetallization. Such demetallization reactions are illustrated by the following equation:

where R is any organic radical, including porphyrins and petroporphyrins, M is any metal, and a is the valence of the metal associated with the organic moiety. Organic complexes of zero-valent metals can also be demetallized by these methods. Illustrative of the organometallic compounds that can be demetallized by reaction with water and/or alcohol according to this method are the porphyrins and petroporphyrins commonly found in petroleum crudes, tar sands oils, shale oils, coal extracts, and the like.

The acid-catalyzed demetallation reactions can be carried out in the presence of an oxidizing agent, such as oxygen, peroxides, ozone, and the like, to oxidize the metal contained in the organometallic compound to a more soluble, higher valence state, if desired. Such oxidative demetallation transformations can be effected by contacting a composition containing the organometallic compound, the chalcogen compound/sulfuric acid component, and the oxidizing agent. Similarly, the valence state of the metal complexed in the organometallic compound can be reduced to produce a more soluble metal ion, e.g., the conversion of ferric to ferrous, by conducting the acid-catalyzed demetallation reaction in the presence of a reducing agent, such as hydrogen, hydrazine, and the like. Such reductive acid-catalyzed demetallation reactions can be carried out by contacting a composition containing the organometallic compound, the chalcogen compound/sulfuric acid component and a reducing agent.

The acid-catalyzed nitration reactions of this invention involve the reaction of organic compounds capable of acid-catalyzed nitration with nitrogen oxides and can be effected by contacting a composition containing the nitratable compound, nitrogen oxides, and the chalcogen compound/sulfuric acid-containing catalyst under nitration conditions. Such reactions are schematically illustrated by equation (12).

R(H)n + nNO2 --> (NO2)nR + nH+ (12)

wherein R is any nitratable organic moiety having a valence of n. Illustrative of nitration reactions that can be carried out in accordance with this invention are the reactions of toluene with nitrogen (II) oxide to produce nitrotoluene and trinitrotoluene (TNT), the nitration of cellulose to produce nitrocellulose, the nitration of alkanes such as n-decane, and the like.

The acid-catalyzed organic reactions discussed above and other acid-catalyzed reactions known in the art can be effected by contacting the organic material to be reacted with the liquid or solid chalcogen compound/sulfuric acid containing catalyst in either the vapor phase, liquid phase or solid phase (as in the case of cellulose, nylon and other solid materials). The liquid catalysts can comprise a melt of the anhydrous chalcogen compound/sulfuric acid catalyst component, or they can comprise a solution of this component in either the organic feedstock or other solvent. The solid catalysts can comprise the chalcogen compound/sulfuric acid component, with or without the optional components described, impregnated or ion exchanged into a solid support. Mixed liquid phase reactions can be carried out by forming emulsions or dispersions of the chalcogen compound/sulfuric acid component melt. or solution and the reactants and/or organic material to be converted. The novel surfactant-containing chalcogen compound/sulfuric acid components of this invention are particularly suitable for use as acid catalysts in the conversion of organic compounds containing significant amounts of lipophilic substances, such as waxes, oils and high molecular weight organic substances. Illustrative of such lipophilic materials are the waxy cuticles on many types of vegetation, proteins, particularly fatty proteins, cellulosic substrates containing lignands and other wood-derived lipophilic substances, and the like.

The acid-catalyzed reactions of this invention can be carried out at any temperature below the thermal decomposition temperature of the chalcogen compound/sulfuric acid component and above the temperature at which the composition comprising the chalcogen compound/sulfuric acid component solidifies. The reaction temperature should also be kept below the temperature at which the organic feedstock, reactants, intermediates or products react with the chalcogen compound/sulfuric acid component. The occurrence of any such side reaction at any given reaction temperature can be readily determined by analyzing the product to determine the presence of byproducts resulting from such side reactions. For example, reaction temperatures used with the urea/sulfuric acid components should be kept below 80°C (176°F) and preferably below about 77°C (170°F) because of the relatively low decomposition temperature of the urea/sulfuric acid component in the presence of water in reactions where a significant amount of water is present. Higher reaction temperatures up to about 150°C (300°F) can be used with urea/sulfuric acid Components may be used under anhydrous conditions when the reaction system is substantially free of water, i.e., when the system contains less than about 2, preferably less than about 1, weight percent water based on the concentration of the urea/sulfuric acid component. However, such higher temperatures, i.e., temperatures above 77°C (170°F), are preferably avoided when the reaction system is not substantially anhydrous, i.e., does not contain a detectable amount of water. The reaction rate increases as the temperature is raised. The thermal decomposition temperature of other hydrous and anhydrous chalcogen compound/sulfuric acid components can be readily determined by gradually raising the temperature of the selected composition until evidence of decomposition occurs, such as effervescence or other vapor evolution and discoloration.

The processes of this invention can be carried out at essentially any pressure and even under vacuum if desired. Vapor phase reactions, i.e., reactions involving organic reactants in the vapor phase, can be accelerated by increasing the pressure on the system. Illustrative reaction pressures are 0 to 2,000 atmospheres, although pressures of 0 to 100 atmospheres are usually sufficient to achieve acceptable reaction rates.

The acid-catalyzed reactions of this invention require contact times of the organic reactants and the sulfuric acid-containing component consistent with the desired product yield. In general, increasing the contact time increases the conversion. Since the reaction rate depends on the nature of the reaction involved, the compatibility of the sulfuric acid-containing component with the reactants, and the operating pressure and temperature, the reaction time should be sufficient to achieve the required degree of conversion. Batch contact times from 1 minute to 100 hours are usually sufficient to achieve complete conversion of most organic substrates. Shorter reaction times will usually occur in continuous processes employing the methods of this invention, in which case it may be desirable to separate unreacted organic materials at the effluent of the reaction zone and recycle these materials to the reaction zone.

The novel compositions and acid-catalyzed processes for converting organic compounds according to this invention have several significant advantages over compositions and processes otherwise available in the art. The chalcogen compound/sulfuric acid components are relatively inexpensive; in addition, they are non-corrosive and stable under normal conditions. They are also highly active protonating agents and can therefore be used to effect the acid-catalyzed conversion of a wide variety of organic compounds without accelerating reactions associated with other acid catalysts, particularly side reactions associated with the use of sulfuric acid, such as oxidation and sulfonation.

The invention is further described by the following examples, which are illustrative of specific ways of practicing the invention and are not intended to limit the scope of the invention as defined by the appended claims.

EXAMPLE 1

This example illustrates the hydrolysis of complex polyethers by demonstrating the complete hydrolysis of cellulose to glucose in the presence of a urea/sulfuric acid component of this invention. Sterile cotton fabric samples are in a urea/sulfuric acid component having a urea/sulfuric acid molar ratio of 1.2 and containing 38.6% urea, 52.1% sulfuric acid and 8.3% water by weight and maintained at a temperature of 21°C (70°F). The cotton cloth samples are added one at a time to about 500 ml of the urea/sulfuric acid component described above and the mixture is stirred throughout the process. Complete dissolution of each cotton cloth sample occurs in about 1 minute. After adding about 20 cotton cloth samples, the mixture becomes more viscous. A portion of the reaction mixture is analyzed by high precision liquid chromatography (HPLC) and found to contain glucose in an amount corresponding to the stoichiometric conversion of the cellulose introduced into the reaction. Neither HPLC analysis nor any other observation during the process shows the occurrence of any reaction other than the hydrolysis of cellulose to glucose. There is no evidence of sulfonation and oxidation of either cellulose or glucose. No fumes are given off during the process and the reaction medium does not discolor.

EXAMPLE 2

This example illustrates the use of a urea/sulfuric acid component of this invention to acid catalyze the hydrolysis of cellulose in living vegetation and the subsequent effectiveness of the chalcogen compound/sulfuric acid components as herbicides.

Four replicate test plots of five acres, each bearing bulbs in the first true leaf stage (about 1 inch high), infested with mallow, cheese weed, nightshade, shepherd's table, Matricaria matricarioides and purslane, will each be treated by applying 470 l/ha (50 gallons per acre) of a urea/sulfuric acid component containing a urea/sulfuric acid molar ratio of about 1.1 and containing 14.6% by weight urea, 20.8% by weight sulfuric acid and 64.6% by weight water. The described treatment results in 95 to 100% kill of all weed species within 48 hours of application. There is no damage to the bulbs as evidenced by the absence of browning of the leaves, spotting or the like. The cellulose structure of the bulb is protected by the waxy cuticles characteristic of green onions, which, however, can also be hydrolyzed by using the surfactant-containing chalcogen compound/sulfuric acid components within the scope of this invention.

EXAMPLE 3

This example illustrates the hydrolysis of polycarboxylic acid esters and demonstrates the depolymerization of protein by contact with the chalcogen compound/sulfuric acid components of this invention. Two cowhide pump seals are contacted with a urea/sulfuric acid component containing 36.5 wt% urea, 52.1 wt% sulfuric acid, and 11.4 wt% water and having a urea/sulfuric acid molar ratio of about 1.1 for about 70 hours at room temperature. The cowhide seals completely dissolve within the 70 hour contact period.

EXAMPLE 4

The procedure of Example 3 is repeated by contacting two cowhide pump seals with a urea/sulfuric acid component containing 21.5 wt.% urea, 55.2 wt.% sulfuric acid and 23.3 wt.% water and having a urea/sulfuric acid molar ratio of about 0.6. These compositions correspond to the formulation 10-0-0-18. The cowhide pump seals dissolve within 70 hours at room temperature.

EXAMPLE 5

This example illustrates the oxidative addition of organic compounds and demonstrates the oxidative addition of propylene in the presence of the chalcogen compound/sulfuric acid components of this invention. Technically pure propylene and air are charged to about 1000 ml of a urea/sulfuric acid component containing 38.6 wt.% urea, 52.1 wt.% sulfuric acid and 9.3 wt.% water and having a urea to sulfuric acid molar ratio of 1.2. The gas mixture is introduced through a gas distributor immersed in the urea/sulfuric acid component maintained at 21°C (70°F) and contained in a 5 L three-neck flask equipped with a stirrer, feed inlet and outlet means. The evaporated liquid phase is removed from the 5L flask and passed through an ice-cooled liquid trap where the reaction product is collected. The liquid phase recovered from the evaporated liquid is analyzed by infrared spectroscopy and found to contain propylene dimers and higher oligomers of propylene containing olefinic unsaturation.

EXAMPLE 6

Propylene and butene are reductively added to each other by introducing gaseous propylene and 2-butene into the liquid phase formed by melting an anhydrous urea/sulfuric acid component containing 42.6 wt.% urea and 47.4 wt.% sulfuric acid and having a urea/sulfuric acid molar ratio of 1.2. The liquid phase is maintained at a temperature of 66ºC (150ºF) and the vapor and liquid phases are maintained at a pressure of 1000 psig. The liquid phase is continuously removed from the reaction zone and flashed to recover vaporizable dimers and higher polymers of propylene and 2-butene and co-polymers of propylene and 2-butene. Higher polymers not removed by flashing can be extracted from the urea/sulfuric acid melt with normal hexane at a pressure sufficient to maintain the normal hexane in the liquid phase. The recovered urea/sulfuric acid component is recycled to the reaction zone.

EXAMPLE 7

Maleic acid is reacted with 1,2-ethanediol (glycol) by stirring a 50:50 molar mixture of maleic acid and glycol with a urea/sulfuric acid component containing 36.5 wt% urea, 52.1 wt% sulfuric acid and 11.4 wt% water and having a urea/sulfuric acid molar ratio of 1.1 at a temperature of 60ºC (140ºF) under a pressure of 100 psig for 10 minutes to produce the corresponding polyester of maleic acid and 1,2-ethanediol. The resulting polymer is extracted from the reaction phase with isopropyl alcohol.

EXAMPLE 8

Benzene is alkylated with a mixture of 1-butene and 2-butene to produce normal and isobutylbenzenes by stirring a mixture of benzene, 1-butene and 2-butene with a molten urea/sulfuric acid component containing 42.6 wt.% urea and 57.4 wt.% sulfuric acid in the presence of an alkylphenol polyethylene oxide surfactant at a temperature of 71°C (160°F) and under a reaction pressure sufficient to maintain the reactants in the liquid phase. The resulting alkylbenzene is purified by centrifuging the resulting reaction phase mixture. Complete separation is achieved by washing the urea/sulfuric acid component melt with toluene.

EXAMPLE 9

Normal butylbenzene is prepared by heating equimolar amounts of 1-chlorobutane and benzene in a molten urea/sulfuric acid component containing 42.6 wt.% urea and 75.4 wt.% sulfuric acid and having a urea/sulfuric acid molar ratio of 1.2 at a temperature of 60°C (140°F) and a pressure of 100 psig for a period of 10 minutes. The n-butylbenzene product is recovered by cooling the reaction mixture to solidify the urea/sulfuric acid component melt and extracting the resulting mixture with toluene. The n-butylbenzene product is removed from the toluene solvent by distilling off the solvent and the urea/sulfuric acid component is remelted and returned to the process.

EXAMPLE 10

A mixture of isooctanes is prepared by contacting normal octane with a molten urea/sulfuric acid component containing 42.6 wt.% urea and 57.4 wt.% sulfuric acid and having a urea/sulfuric acid molar ratio of 1.2 at a temperature of 71°C (160°F) under a pressure of 500 psig for 5 minutes. The resulting isooctane mixture is recovered by cooling the melt to a temperature of 21°C (70°F) to solidify the molten mixture and extracting the isooctane product with normal hexane. The resulting solution of hexane and isooctane is separated by distillation and urea/sulfuric acid is melted and recycled to the reaction zone.

EXAMPLE 11

A crude petroleum containing organometallic compounds comprising petroporphyrins is demetallized by contacting the crude petroleum with an aqueous urea/sulfuric acid component containing 36.5 wt% urea, 52.1 wt% sulfuric acid and 11.4 wt% water and having a urea/sulfuric acid molar ratio of 1.1 in the presence of oxygen at a temperature of 71°C (160°F) and a pressure of 500 psig with sufficient agitation to intimately mix the crude petroleum and the urea/sulfuric acid component. The resulting reduced metal crude oil is recovered from the urea/sulfuric acid component by decantation, washed with water to remove residual urea, sulfuric acid and metal salts, and dried by distillation.

EXAMPLE 12

Benzene is nitrated by forming a dispersion of benzene in a solution of a urea/sulfuric acid component having a urea/sulfuric acid molar ratio of 1.1 and containing 15.9 wt% urea and 22.7 wt% sulfuric acid in water with sufficient agitation to produce an intimate dispersion of the benzene and the urea/sulfuric acid component solution. Nitrous oxide is dispersed into the stirred mixture of benzene and the urea/sulfuric acid component and the resulting mixture is contacted at a temperature of 66°C (150°F) and a pressure of 200 psig. The resulting nitrated benzene product is recovered by cooling the reaction mixture and extracting the nitrated benzene product with toluene.

EXAMPLE 13

The mono-N-allyl-thioformamide adduct of sulfuric acid is prepared by placing 50 g of N-allylthioformamide in a 500 ml flask, cooled to 10ºC (50ºF), and then gradually adding 51 g of 89% sulfuric acid, precooled to -1ºC (30ºF), at a rate sufficiently slow to maintain the mixture in the flask at a temperature below 10ºC (50ºF). 200 ml of water are added to the flask and the mixture is allowed to equilibrate at room temperature 21ºC (70ºF). Cotton fabric samples are then submerged in the mixture at room temperature and held for 24 hours to hydrolyze the cellulose in the cotton.

EXAMPLE 14

21 g of 98 wt% sulfuric acid and 50 g of 1-(4-aminobenzenesulfonyl)-2-thiourea are mixed using the procedures described in Example 13 to produce the corresponding equimolar adduct dissolved in the ether/water mixture, which can be used to hydrolyze cellulose.

EXAMPLE 15

30 g of 98 wt% sulfuric acid and 50 g of 1-benzylurea are mixed using the procedure described in Example 13 to form the corresponding equimolar adduct dissolved in the ether/water mixture, which can be used to hydrolyze cellulose.

EXAMPLE 16

15.5 g of 98 wt% sulfuric acid and 50 g of 1,3 bis(2-ethoxyphenyl)carbamide are mixed using the procedure described in Example 13 to form the corresponding equiomolar adduct dissolved in the ether/water mixture which can be used to hydrolyze cellulose as described in Example 13.

EXAMPLE 17

22 g of 98 wt% sulfuric acid and 50 g of 1-(2-bromo-3-methylbutanoyl)carbamide are mixed using the procedure described in Example 13 to produce the corresponding equimolar adduct, dissolved in the ether/water mixture, which can be used to hydrolyze cellulose.

EXAMPLE 18

23 g of 98 wt% sulfuric acid and 50 g of 1-(4-bromophenyl)carbamide are mixed using the procedure described in Example 13 to form the corresponding equimolar adduct dissolved in the ether/water solution which can be used to hydrolyze cellulose as described in Example 13.

EXAMPLE 19

34 g of 98 wt% sulfuric acid and 50 g of 1,3-diacetyl carbamide are mixed using the procedure described in Example 13 to form the corresponding equimolar adduct dissolved in the ether/water solution. Propylene and air are bubbled through the solution at a temperature of 32ºC (30ºF) and a pressure of 50 psi to form propylene dimers and higher oligomers.

EXAMPLE 20

32.5 g of 98 wt.% sulfuric acid and 50 g of 1-ethyl-2-selenourea are mixed using the procedure described in Example 13 to obtain the corresponding equimolar adduct dissolved in the ether/water solution. Cowhide pump seals can be immersed in the solution which is maintained at 38ºC (100ºF) for 24 hours to partially hydrolyze the cowhide protein.

Although particular embodiments of this invention have been described, it will of course be understood that the invention is not so limited, that many obvious modifications may be made, and it is intended to include in this invention all such modifications as come within the spirit and scope of the appended claims.

Claims (37)

1. A process for carrying out the acid-catalyzed reaction, other than hydrolysis, of an organic compound, which reaction can be acid-catalyzed by sulfuric acid, which comprises the steps of: carrying out said reaction in the presence of a catalytically active amount of the monoadduct of sulfuric acid and a chalcogen-containing compound having the empirical formula R₁- -R₂ wherein X is a chalcogen, R₁ and R₂ are each independently selected from the group consisting of hydrogen, NR₃R₄ and NR₅, at least one of R₁ and R₂ is other than hydrogen, R₃ and R₄ are independently selected from hydrogen and monovalent organic radicals, and R₅ is a divalent organic radical. 2. A process for carrying out the acid-catalyzed reaction of an organic compound, which reaction can be acid-catalyzed by sulphuric acid, which comprises the steps: carrying out said reaction in the presence of a catalytically active amount of the monoadduct of sulphuric acid and a chalcogen-containing compound, other than urea, with the empirical formula R₁- -R₂ wherein X is a chalcogen, R₁ and R₂ are each independently selected from the group consisting of hydrogen, NR₃R₄ and NR₅, at least one of R₁ and R₂ is other than hydrogen, R₃ and R₄ are each independently selected from hydrogen and monovalent organic radicals, and R₅ is a divalent organic radical. 3. A method according to claim 1 or 2, characterized in that said organic compound is different from plant material. 4. A process according to claim 1, 2 or 3, characterized in that said adduct is free from thermal decomposition products of sulfuric acid and said chalcogen-containing compound. 5. Process according to one of claims 1 to 4, characterized in that said reaction is carried out at a temperature below the thermal decomposition temperature of said adduct. 6. Process according to one of claims 1 to 5, characterized in that said adduct composition is free from sulfuric acid not bound in the adduct. 7. The method of claim 1, characterized in that said chalcogen-containing compound is selected from the group consisting of urea, thiourea, formamide and combinations thereof. 8. Process according to one of claims 1 to 7, characterized in that the process comprises alkylating an alkylatable organic compound according to the formula R6; + R₇-CH=CH-R₇ --> R6-H-CH2-R8; wherein R₇ and R₈ are independently selected from hydrogen and monovalent organic radicals and R₆ is an alkylatable organic compound. 9. The process of claim 8 wherein R7 and R8 are independently selected from hydrogen and alkyl radicals having 1 to 10 carbon atoms and R6 is selected from the group consisting of alkanes, aromatics, alkylaromatics and arylalkanes having 4 to 20 carbon atoms and combinations thereof. 10. Process according to one of claims 1 to 7, characterized in that said reaction comprises the oxidative addition of hydrocarbons according to the formula R6H + R7H + 1/2O2 --> R6R7 + H2O wherein R₆ and R₇ are hydrocarbon radicals. 11. Process according to claim 10, characterized in that R₆ and R₇ are hydrocarbon radicals having 1 to 40 carbon atoms. 12. The process of claim 10 or 11, characterized in that R6 and R7 are independently selected from hydrocarbon radicals of the group consisting of alkanes, alkenes, alkynes, aromatics, alkyl-, alkenyl- and alkynyl-substituted aryls and aryl-substituted alkanes, alkenes and alkynes. 13. Process according to claim 10 or 11, characterized in that at least one of the groups R₆ and R₇ is an olefin. 14. Process according to claim 10 or 11, characterized in that at least one of the groups R₆ or R₇ is an alpha-olefin. 15. Process according to claim 10 or 11, characterized in that R₆ and R₇ are identical or different alpha-olefins with up to 40 carbon atoms. 16. The method of any one of claims 1 to 7, characterized in that said reaction comprises forming an ester selected from the group consisting of carboxylic acid esters, thioesters and combinations thereof by reacting an acid selected from the group consisting of carboxylic acids, thioacids and combinations thereof with a compound selected from the group consisting of alcohols, thiols and combinations thereof. 17. A process according to any one of claims 1 to 7, characterized in that said reaction comprises the formation of a compound selected from the group consisting of carboxylic acid esters, thioesters and combinations thereof according to the formula R6- -YH + R7ZH --> R6- -Z-R7; + H2Y in which R6 and R7 are organic radicals and Y and Z are independently selected from O and S. 18. A process according to any one of claims 1 to 7, characterized in that said reaction comprises the preparation of a compound selected from the group consisting of carboxylic acid esters, Thioesters and combinations thereof, according to one or more of the formulas B, C or D wherein R6, R7, R8 and R9 are the same or different organic radicals and Y and Z are independently selected from O and S. 19. A process according to any one of claims 1 to 7, characterized in that said reaction comprises the acid-catalyzed polymerization of an organic compound having at least one carbon-carbon double bond capable of undergoing acid-catalyzed polymerization according to the formula in which n is an integer greater than 1 and R₆ and R₇ are independently selected from hydrogen and monovalent organic radicals. 20. A process according to any one of claims 1 to 7, characterized in that said reaction comprises polymerizing olefins according to the formula wherein n is an integer greater than 1 and R6 and R7 are independently selected from hydrogen and hydrocarbon radicals. 21. A process according to claim 19 or 20, characterized in that R6 and R7 are independently selected from hydrogen and hydrocarbon radicals having 1 to 10 carbon atoms. 22. A process according to claim 19, 20 or 21, characterized in that said reaction is carried out in the absence of an oxidizing agent. 23. A process according to any one of claims 1 to 7, characterized in that said reaction comprises the acid-catalyzed reduction of an organic compound, said process comprising the step of carrying out said reaction in the absence of oxidizing agents and in the presence of a reducing agent. 24. A process according to any one of claims 1 to 7, characterized in that said reaction comprises hydrogenating an organic compound containing unsaturation selected from the group consisting of olefinic, alkynylic and aromatic unsaturation and combinations thereof, which comprises reacting said organic compound with hydrogen in the absence of oxidizing agents. 25. The process of claim 23 or 24, characterized in that said reaction is carried out in the presence of a hydrogenation component selected from the group consisting of hydrogen, hydrazine and combinations thereof. 26. The method of claim 24, characterized in that said organic compound is selected from the group consisting of benzene, alkynes and alkyl and alkenyl aromatic compounds. 27. Process according to claim 25, characterized in that said organic compound is selected from olefinically unsaturated organic compounds having 2 to 40 carbon atoms. 28. A process according to any one of claims 1 to 7, characterized in that said reaction comprises the dimerization, oligomerization and/or polymerization of olefinically unsaturated organic compounds according to the formula and/or higher polymers, wherein R₆-CH=CH-R₇ and R�8-CH=CH-R�9 are independently selected from alkenes and alkenyl aromatic compounds. 29. A process according to claim 28, characterized in that R₆, R₇, R₈ and R₆ are independently selected from hydrogen and alkyl radicals having 1 to 20 carbon atoms. 30. Process according to claim 28, characterized in that said alkenes and alkenyl aromatic compounds have up to 20 carbon atoms. 31. Process according to one of claims 1 to 7, characterized in that said reaction comprises the nitration of an organic compound according to the formula R(H)n + nNO2 --> (NO2)nR + nH+ wherein R is a nitratable organic moiety having a valence of n. 32. The method of claim 31, characterized in that said organic compound is selected from the group consisting of alkanes, toluene, cellulose and combinations thereof. 33. A process according to any one of claims 1 to 7, characterized in that said reaction comprises isomerizing hydrocarbons having 4 or more carbon atoms by contacting said hydrocarbons with said adduct under isomerizing conditions. 34. Process according to claim 33, characterized in that said hydrocarbons have 4 to 20 carbon atoms. 35. Method according to one of claims 1 to 7, characterized in that that said reaction involves the demetallization of an organometallic compound of the formula (R)aMa according to the formula (R)aMa + aH&spplus; --> aRH + M+a wherein R is an organic radical, M is a metal, and (a) the valence of the metal is M, the process comprising reacting said organometallic compound with a compound selected from the group consisting of water, alcohol, and combinations thereof, in the presence of a catalytically active amount of said adduct. 36. The method of claim 35, characterized in that said reaction comprises demetallizing a composition comprising a moiety selected from the group consisting of metal-containing porphyrins, petroporphyrins, and combinations thereof, which comprises reacting said composition with a compound selected from the group consisting of water, alcohol, and combinations thereof in the presence of a catalytically active amount of said monoadduct. 37. Process according to claim 2, characterized in that said reaction comprises the hydrolysis of carboxylic acid esters, proteins and/or polysaccharides by reaction with water in the presence of said adduct.