WO2020082914A1 - Preparation for organic phosphorus compound by condensation of mes-trimethyl trihalomethyl benzene and diphenyl phosphine oxide - Google Patents

Abstract

Involved is the field of photocuring functional new material chemicals. First disclosed are a "one-pot" direct condensation reaction of mes-trimethyl trihalomethyl benzene (also known as "2,4,6-trimethyl-1-trihalomethyl-benzene") and diphenyl phosphine oxide, and an efficient preparation for mes-trimethyl benzoyl diphenyl phosphine oxide (also known as "2,4,6-trimethyl benzoyl diphenyl phosphine oxide") using reaction process technology. The process technology possesses the characteristics of an outstanding low-cost economic competitiveness and being environmentally friendly. The compound is a widely used photosensitive initiator containing an olefinic bond (C=C) unsaturated radiation polymerizable system.

Description

Preparation of Organic Phosphine Compounds by Condensation of Methmethyltrihalomethylbenzene and Diphenylphosphine Oxide 【Technical Field】

The present invention relates to the field of photocuring new material chemicals, and for the first time disclosed mesitylene trihalomethylbenzene (also known as "2,4,6-trimethyl-1-trihalomethyl-benzene") and The "one-pot" direct condensation reaction of phenylphosphine oxide, and the efficient preparation of mesitylene diphenylphosphine oxide (also known as "2,4,6-trimethylbenzoyl" Acyl diphenyl phosphine oxide "). The process technology has outstanding low-cost economic competitiveness and environmental friendly characteristics. The compound is a widely used photoinitiator of ethylenic (C = C) unsaturated radiation-polymerizable system.

【Background technique】

Organic phosphine compounds are widely used new materials and fine chemicals, especially in the field of radiation curing new materials industry. They are the key additive compounds of the photoinitiator, such as the important commercially available compound trimethylbenzoyl di Phenylphosphine oxide [CAS registration number 75980-60-8, English name 2,4,6-Trimethylbenzoyldiphenylphosphine Oxide] is a well-known "Acylphosphine Oxide type" containing Lucene-TPO as the representative brand in the industry. Highly efficient photo-initiator of bond-unsaturated radiation-polymerizable system, which is used in photocurable wood coatings, train and subway coatings, printing and packaging inks, adhesives, corrosion protection, composite materials, optical fibers, and TFT-LCD liquid crystals. Display and other fields have a wide range of applications. In view of its outstanding practical value, the industry has been continuously exploring its new more competitive and environmentally friendly preparation process technology.

The existing process technology for the preparation of target compounds of mesitylene diphenylphosphine oxide is mainly divided into the so-called acid chloride route or aromatic aldehyde route. As shown in the figure below, the former uses the condensation reaction of arylphosphane and key raw material 2,4,6-trimethylbenzoyl chloride (patent CN1198831), or the metal salt of arylphosphane and 2,4,6- Condensation reaction of trimethylbenzoyl chloride (patents CN1211388 and CN105541913), or Arbuzov-Michaelies condensation reaction of arylphosphonates and 2,4,6-trimethylbenzoyl chloride (patents US4710523 and US4324744). The latter uses diphenylphosphine oxide and 2,4,6-trimethylbenzaldehyde to first add and condense to prepare the corresponding secondary alcohol intermediate, and then prepare the target product through the oxidation reaction catalyzed by the transition metal complex.

The above-mentioned known documents and technologies have been proved by practice to have significant process defects one by one, including but not limited to the following aspects: high cost of the process route, many environmentally hazardous wastes, the use of alkali or organometallic reagents that are highly air sensitive and therefore expensive and dangerous ; Use highly air-sensitive and foul-smelling organophosphane raw materials or intermediates; use highly polluting transition metal oxidation catalysts or promoters; use explosion-proof inorganic or organic peroxides as terminal oxidants or promoters, and / or Or process emissions of methyl chloride (CH ₃ Cl) or ethyl chloride (CH ₃ CH ₂ Cl) and other international laws and regulations (Montreal International Convention) expressly strictly control the atmospheric ozone-depleting (O ₃ ) hazardous chemicals. At the same time, further, the key raw materials of the above process route 2,4,6-trimethylbenzoyl chloride and 2,4,6-trimethylbenzaldehyde, their own manufacturing also has the disadvantage of high cost economic competition And highlight the risks of environmental protection governance.

Therefore, there is still a need for continuous strengthening of technological innovation in the industry to specifically address the outstanding environmental governance, safe operation, and cost control issues faced by the current production of mesitylene. In fact, since 2016, China ’s strengthened legislation and enforcement of environmental protection has triggered a major rectification of the national chemical industry, which directly caused the shutdown and transfer of high-pollution production capacity including products covered by this application, which has caused an unprecedented supply chain crisis in the market. .

[Invention content]

This application has for the first time discovered unexpectedly that, as shown in the following reaction formula (I), the organic phosphine photoinitiator compound trimethylbenzoyldiphenylphosphine oxide can pass 2,4,6-trimethyl-1 -Trichloromethyl-benzene (A) and inexpensive and readily available diphenylphosphine oxide [marked as compound B, which has the molecular formula Ph ₂ P (O) H (B1) or Ph ₂ P (OH) (B2 ) Tautomers] a new one-pot synthesis process that is directly condensed under suitable reaction conditions and is convenient, safe and highly environmentally friendly and economical to prepare.

The conditions are any combination of solvents, temperature, pressure, and / or additives, or any two or more of them.

The reaction "solvent" involved in this process is selected from substituted or unsubstituted aromatic hydrocarbons containing 1-24 carbons, linear or branched aliphatic hydrocarbons, amides, ethers, esters, ketones, nitriles, carboxylic acids, water, Amine, ionic liquid, supercritical carbon dioxide, or a mixed solvent composed of any two or more of the above types of solvents; preferred solvents are methylene chloride, dichloroethane, chloroform, carbon tetrachloride, benzene, toluene, dichloromethane Toluene, trimethylbenzene, tetramethylbenzene, ethylbenzene, diethylbenzene, chlorobenzene, dichlorobenzene, anisole, nitrobenzene, heptane, hexane, petroleum ether, dioxane, tetrahydrofuran, methyl tert-butyl Ether, ethylene glycol dimethyl ether, bisglycol dimethyl ether, triethylene glycol dimethyl ether, propylene glycol methyl ether acetate, triethylamine, tributylamine, dimethylisopropylamine, pyridine, N, N-tetramethylethylenediamine, N-alkylmorpholine, N-alkylpyrrole, N, N-dimethylformamide, formylmorpholine, N, N-diethylformamide, N -Methylpyrrolidone, or a mixed solvent composed of any two or more of the above solvents.

The reaction "temperature" involved in this process is selected from -70 degrees Celsius to 200 degrees Celsius, preferably selected from -30 degrees Celsius to 180 degrees Celsius, and more preferably selected from -20 degrees Celsius to 150 degrees Celsius.

The reaction "pressure" involved in this process is selected from 0.001 to 200 standard atmospheres, preferably from 0.1 to 100 standard atmospheres, and more preferably from 0.1 to 20 standard atmospheres.

The reaction "additives" involved in this process encompass reaction accelerators, synergists, catalysts, and / or functional aids, which are Lewis acids or bases (Lewis acids / bases) elements or compounds, preferably alkali metals , Alkaline earth metals, main group metals, or transition metal fluorides, chlorides, bromides, iodides, oxides, hydroxides, sulfides, alkoxides, alkyl or aryl metal compounds; or alkali metals, Alkaline earth metals, main group metals, or transition metal carbonates, bicarbonates, sulfites, bisulfates, sulfonates, or carboxylates; or alkali metals, alkaline earth metals, or transition metals in one or more units Organic phosphorus, organic amine, hydroxyl, ketone carbonyl, ester carbonyl, or carboxylic acid ligand complex; or tetraalkylammonium halide, tetraalkylammonium hydroxide, or ionic liquid (Ionic Liquids); or inorganic protonic acid, Organic carboxylic acid, organic sulfonic acid, heteropoly acid, molecular sieve, zeolite, diatomaceous earth, montmorillonite, kaolin; or boron, silicon, phosphorus element fluoride, chloride, bromide, iodide, oxide, hydrogen Oxides, sulfur Compounds, alkoxides; or mixtures or combinations of any two or more of the above-defined "additives". Based on the molar equivalent of the reaction raw materials, the amount of the "additive" used may be a catalytic amount, an equivalent amount, or an excessive amount. .

Whereas diphenylphosphine oxygen can be carried out in situ from the commercially available diphenylphosphine halide Ph ₂ PY (C) and reagents in the form of M (OH) _n for the alkaline hydrolysis or hydrolysis reaction disclosed in the previous invention (CN2018110370056) Synthesized or prepared in advance, this reaction can also be achieved by the following reaction formula (II). Where Y is Cl or Br; M in M (OH) _n is hydrogen, NH ₄ , or a monovalent or n-valent metal ion, and n is an integer between 1-6. Preferred M (OH) _n is water, NH ₄ OH, sodium hydroxide, potassium hydroxide, aluminum hydroxide, magnesium hydroxide, lithium hydroxide, calcium hydroxide, copper hydroxide, iron hydroxide, or barium hydroxide , Or a mixture of any two or more of the above. Conditions are defined as above.

Further, since the raw material 2,4,6-trimethyl-1-trichloromethyl-benzene can be conveniently added from mesitylene and carbon tetrachloride through the method reported in the earlier disclosure document (CN102875598) of the present owner. Preparation, as shown in formula (III), the invention can also produce mesitylene, carbon tetrachloride, and diphenylphosphine oxide under "single-pot" reaction under appropriate conditions to produce the target product. Conditions are defined as above.

Furthermore, as shown in formula (IV), by reacting basic raw materials mesitylene, carbon tetrachloride, diphenylphosphine halide Ph ₂ PY, and M (OH) n, the in-situ prepared 2, 4, 6-Trimethyl-1-trichloromethyl-benzene (A) and diphenylphosphine oxide (B1 / B2), with or without intermediate purification, are directly condensed to produce the target product.

Among them, M (OH) n, Ph ₂ PY, and conditions are as defined above.

In summary, by first realizing the condensation reaction of 2,4,6-trimethyl-1-trichloromethyl-benzene and diphenylphosphine oxide, the (I-IV) reaction process disclosed in the present invention unexpectedly reveals The preparation process of trimethylbenzoyldiphenylphosphine oxide, the most simple, efficient and environmentally friendly low-cost organic phosphine functional chemical to date, has been introduced.

In the examples we will further explain.

【detailed description】

The gist of the present invention is further described below in conjunction with specific embodiments:

Example one:

Under a room temperature and under the protection of nitrogen, 20 ml of dry toluene, 4.04 g of diphenylphosphorus oxide, 4.8 g of 2,4,6-trimethyl-1-trichloromethyl-benzene, and 36 mg of anhydrous ferric chloride, the system was heated to 90 ℃ and stirred for three hours (note that the hydrochloric acid tail gas generated by the reaction is absorbed with lye). The system was returned to room temperature, and 20 ml of water and 5 ml of saturated sodium bicarbonate aqueous solution were added successively for shaking and washing. The organic phase was separated, dried, filtered and concentrated. The crude product was chromatographed on silica gel column chromatography to obtain mesitylene Diphenylphosphine oxide light yellow pure product 6.20 g, yield 89%.

Example 2:

Under the protection of room temperature and nitrogen, 38.3 g of carbon tetrachloride and 6.67 g of anhydrous aluminum trichloride were added in sequence in a 100 ml flask, after fully stirring for 15 minutes, 5 g was slowly added dropwise at this temperature within one hour The mesitylene, and then heated to about 40 ℃ and continued stirring for two hours (note that the hydrochloric acid tail gas generated by the reaction is absorbed with lye). After the reaction is complete, the system drops to zero. Slowly add a mixture of 20 ml of water and 5 ml of concentrated hydrochloric acid. Note that the internal temperature does not exceed room temperature. Continue stirring for half an hour. Stand still and separate. The aqueous phase is extracted with 20 ml of carbon tetrachloride. Twice, the organic phases were combined, and the organic phase was washed twice with 100 ml of water, and the layers were separated at rest. The organic phase was dried over sodium sulfate, and concentrated to recover the solvent. The resulting product was directly purified without further purification. Phenylphosphine oxide, following the operation of Example 1, was reacted in toluene to obtain 5.5 g of mesitylbenzoyldiphenylphosphine oxide as a pale yellow pure product with a yield of 84%.

Example three:

Under room temperature and nitrogen protection, add 2.9 grams of powdered potassium hydroxide to dry 60 milliliters of toluene, then slowly add 11.0 grams of diphenylphosphorus chloride dropwise in about half an hour, gradually warm up to 100 degrees Celsius with stirring React for two hours. The potassium chloride solid was removed by filtration under nitrogen protection, and the resulting filtrate was directly mixed with 11.9 g of 2,4,6-trimethyl-1-trichloromethyl-benzene and 95 mg of anhydrous ferric chloride, and the system was maintained The temperature was fully stirred at around 90 ° C (note that the hydrochloric acid tail gas generated by the reaction was absorbed with lye) and the reaction was followed to the end by TLC thin layer chromatography. The system was returned to room temperature, and 50 ml of water and 20 ml of saturated sodium bicarbonate aqueous solution were added successively for shaking and washing. The organic phase was separated, dried, filtered and concentrated. The crude product was chromatographed on silica gel column chromatography to obtain mesitylene Light yellow pure product of diphenylphosphine oxide 15.8g, yield 91%.

Example 4:

Under room temperature and nitrogen protection, 25 ml grams of carbon tetrachloride and 4.9 grams of anhydrous aluminum trichloride were sequentially added to a 100 ml flask. After fully stirring for 15 minutes, 3.7 was slowly added dropwise at this temperature within one hour Gram of mesitylene, and then heated to about 40 ℃ and continued to stir for two hours (note that the hydrochloric acid tail gas generated by the reaction is absorbed with lye). After the reaction is complete, the system drops to zero. Slowly add a mixture of 20 ml of water and 4 ml of concentrated hydrochloric acid. Note that the internal temperature does not exceed room temperature. Continue stirring for half an hour. Stand still and separate. The aqueous phase is extracted with 20 ml of carbon tetrachloride. Twice, the organic phases were combined, and the organic phase was washed twice with 100 ml of water, and the layers were separated at rest. The organic phase was dried over sodium sulfate, and concentrated to recover the solvent. The resulting product was used without purification. Under room temperature and nitrogen protection, add 1.8 g of powdered potassium hydroxide to another 50 ml of toluene in another flask, and slowly add 6.8 g of diphenylphosphorus chloride slowly for about half an hour. Stir and hold for two hours at 100 degrees Celsius. The potassium chloride solid was removed by filtration under the protection of nitrogen, and the resulting filtrate was directly assisted with 2,4,6-trimethyl-1-trichloromethyl-benzene intermediate prepared above and 60 mg of anhydrous with the help of a little toluene dissolution Ferric trichloride is mixed, the system is maintained at a temperature of about 90 ° C and fully stirred (note that the hydrochloric acid tail gas generated by the reaction is absorbed with lye) and the reaction is followed to the end by TLC thin layer chromatography. The system was returned to room temperature, and an equal volume of water and half-saturated aqueous sodium bicarbonate solution were added to the organic phase for shaking and washing. The organic phase was separated, dried, filtered and concentrated. The crude product was chromatographed on silica gel column chromatography to obtain mesitylene The light yellow pure product of benzoyldiphenylphosphine oxide is 8.7 g, and the yield is 81%.

Example 5:

Under the protection of room temperature and nitrogen, 0.4 g of diphenylphosphine oxide, 0.24 g of mesitylene, 5 ml of carbon tetrachloride, and 70 mg of triacetylacetone iron complex catalyst were added in a pressure-sealed tube in sequence The system was sealed and heated to 130 degrees Celsius to react overnight. After the system returned to room temperature, 5 ml of water and 5 ml of saturated aqueous sodium bicarbonate solution were added successively for shaking and washing. The organic phase was separated, dried, filtered and concentrated. The crude product was chromatographed on silica gel column chromatography to obtain mesitylene Acyl diphenyl phosphine oxide light yellow pure product 0.36g, yield 52%.

It should be emphasized that the above-mentioned embodiments are merely exemplary rather than restrictive descriptions. Based on the disclosure of this application, any adjustments or changes in reaction conditions or parameters that may be commonly adopted by technical practitioners will not deviate from the gist of the present invention. The scope of protection of this patent shall be subject to the relevant rights record.

Claims (10)

1. The organic phosphine compound is trimethyl benzoyl diphenyl phosphine oxide preparation method, the method by the following reaction formula (I), via 2,4,6-trimethyl-1-trichloromethyl-benzene (A ) And diphenylphosphine oxide [labeled as compound B, which has a tautomer of the formula Ph ₂ P (O) H (B1) or Ph ₂ P (OH) (B2)] under appropriate reaction conditions Direct condensation "one-pot method" synthesis.

   The conditions are a combination of any one or any two or more of solvents, temperature, pressure, and / or additives.

   
2. The preparation method of the organic phosphine compound trimethyl benzoyl diphenyl phosphine oxide, the method of generating in situ through Ph ₂ PY (C) and the reagent in the form of M (OH) _n Phenylphosphine oxide, which is then synthesized with 2,4,6-trimethyl-1-trichloromethyl-benzene (A) by direct condensation under "reaction conditions" in a "one-pot method".

   Where Y is Cl or Br; M in M (OH) _n is hydrogen, NH ₄ , or a monovalent or n-valent metal ion, and n is an integer between 1-6. Preferred M (OH) _n is water, NH ₄ OH, sodium hydroxide, potassium hydroxide, aluminum hydroxide, magnesium hydroxide, lithium hydroxide, calcium hydroxide, copper hydroxide, iron hydroxide, or barium hydroxide , Or a mixture of any two or more of the above. The conditions are a combination of any one or any two or more of solvents, temperature, pressure, and / or additives.

   
3. Preparation method of organic phosphine compound mesityl benzoyl diphenyl phosphine oxide, the method generates in-situ 2,4,6-trimethyl via mesitylene and carbon tetrachloride through the following reaction formula (III) -1-Trichloromethyl-benzene (A), which is then synthesized by the "one-pot method" of direct condensation with diphenylphosphine oxide (B1 / B2) under reaction conditions.

   The conditions are a combination of any one or any two or more of solvents, temperature, pressure, and / or additives.

   
4. The preparation method of the organic phosphine compound trimethyl benzoyl diphenyl phosphine oxide, the method by the following reaction formula (IV), through the basic raw materials mesitylene, carbon tetrachloride, diphenylphosphine halide Ph ₂ PY React with M (OH) n to make 2,4,6-trimethyl-1-trichloromethyl-benzene (A) and diphenylphosphine oxide (B1 / B2) prepared in situ with or without The intermediate is purified and synthesized by the "one-pot method" of direct condensation under reaction conditions.

   

   Where Y is Cl or Br; M in M (OH) _n is hydrogen, NH ₄ , or a monovalent or n-valent metal ion, and n is an integer between 1-6. Preferred M (OH) _n is water, NH ₄ OH, sodium hydroxide, potassium hydroxide, aluminum hydroxide, magnesium hydroxide, lithium hydroxide, calcium hydroxide, copper hydroxide, iron hydroxide, or barium hydroxide , Or a mixture of any two or more of the above. The conditions are a combination of any one or any two or more of solvents, temperature, pressure, and / or additives.
5. According to the preparation methods described in claims 1-4, the reaction "solvent" is selected from substituted or unsubstituted aromatic hydrocarbons containing 1 to 24 carbons, linear or branched aliphatic hydrocarbons, amides, ethers and esters , Ketones, nitriles, carboxylic acids, water, amines, ionic liquids, supercritical carbon dioxide, or a mixed solvent composed of any two or more of the above types of solvents; preferred solvents are methylene chloride, dichloroethane, chloroform, Carbon tetrachloride, benzene, toluene, xylene, trimethylbenzene, tetramethylbenzene, ethylbenzene, diethylbenzene, chlorobenzene, dichlorobenzene, anisole, nitrobenzene, heptane, hexane, petroleum ether, dichloromethane Oxyhexane, tetrahydrofuran, methyl tert-butyl ether, ethylene glycol dimethyl ether, bisglycol dimethyl ether, triethylene glycol dimethyl ether, propylene glycol methyl ether acetate, triethylamine, tributyl Amine, dimethylisopropylamine, pyridine, N, N-tetramethylethylenediamine, N-alkylmorpholine, N-alkylpyrrole, N, N-dimethylformamide, formylmorpholine, N , N-diethylformamide, N-methylpyrrolidone, or a mixed solvent composed of any two or more of the above solvents.
6. According to the preparation methods described in claims 1-4, the reaction "temperature" is selected from -70 degrees Celsius to 200 degrees Celsius, preferably selected from -30 degrees Celsius to 180 degrees Celsius, more preferably selected from Between -20 degrees Celsius and 150 degrees Celsius.
7. According to the preparation methods described in claims 1-4, the reaction "pressure" is selected from 0.001 to 200 standard atmospheres, preferably from 0.1 to 100 standard atmospheres, more preferably from Between 0.1 and 20 standard atmospheres.
8. According to the preparation methods described in claims 1-4, the reaction "additives" encompass reaction accelerators, synergists, catalysts, and / or functional assistants, which are Lewis acids or Lewis acids / bases ) Elemental or compound, preferably alkali metal, alkaline earth metal, main group metal, or transition metal fluoride, chloride, bromide, iodide, oxide, hydroxide, sulfide, alkoxide, alkyl Or aryl metal compound; or alkali metal, alkaline earth metal, main group metal, or transition metal carbonate, bicarbonate, sulfite, bisulfate, sulfonate, or carboxylate; or alkali metal, Alkaline earth metal, or transition metal monobasic or polybasic organic phosphorus, organic amine, hydroxyl, ketone carbonyl, ester carbonyl, or carboxylic acid ligand complex; or tetraalkylammonium halide, tetraalkylammonium hydroxide, or ionic liquid (Ionic Liquids); or inorganic protonic acid, organic carboxylic acid, organic sulfonic acid, heteropoly acid, molecular sieve, zeolite, diatomaceous earth, montmorillonite, kaolin; or fluoride, chloride, boron, silicon, phosphorus Bromide, , Oxides, hydroxides, sulfides, alkoxides; or a mixture of more satisfying "additive" in any two, or both, as defined above, or a combination. Based on the molar equivalent of the reaction raw materials, the amount of the "additive" used may be a catalytic amount, an equivalent amount, or an excessive amount.
9. According to the preparation methods described in claims 1-4, respectively, and the "additives" described in claim 8, the preferred additives are ferric chloride, triacetylacetonate iron complex, aluminum trichloride, zinc chloride, magnesium chloride , Indium chloride, copper chloride, rare earth metal chloride, or boron trifluoride, boron trichloride, boric acid, silicon tetrachloride, phosphorus trichloride, phosphorus pentachloride, methanesulfonic acid. More preferred additives are (anhydrous) ferric chloride, (anhydrous) aluminum trichloride, rare earth metal chloride, and triacetylacetone iron complex.
10. The mesitylene benzoyldiphenylphosphine oxide compound prepared according to the preparation methods described in claims 1-4 respectively is used as a photoinitiator in an unsaturated radiation-containing polymerization system containing an ethylenic bond (C = C) the use of.