JP2014058488A - Method for producing 1,1,1,4,4,4-hexafluoro-2-butyne - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an efficient method for producing 1,1,1,4,4,4-Hexafluoro-2-butyne which is appropriate for a flow-through reaction.SOLUTION: There is obtained 1,1,1,4,4,4-Hexafluoro-2-butyne by dechlorinating 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane with a catalyst, followed by isomerization with a catalyst, and 1,1,1,4,4,4-Hexafluoro-2-butyne is efficiently obtained by carrying out all steps by means of a flow-through catalytic reaction.

Description

  The present invention relates to a method for producing 1,1,1,4,4,4-hexafluoro-2-butyne, and in particular, 1,2-dichloro-1,2,3,3,4,4-hexafluoro The present invention relates to a method for producing 1,1,1,4,4,4-hexafluoro-2-butyne from cyclobutane via hexafluorocyclobutene.

  In general, fluorine compounds are widely used industrially such as polymer materials, refrigerants, cleaning agents, pharmaceuticals, and agricultural chemicals. The present invention targets unsaturated fluorine compounds, particularly fluorocyclobutene and 1,1,1,4,4,4-hexafluoro-2-butyne, which are also promising for the above uses.

  As a method for producing 1,1,1,4,4,4-hexafluoro-2-butyne, isomerization reaction of hexafluorobutadiene is known (Non-patent Document 1). Since it is expensive and further uses powdered aluminum chlorofluoride, it is not suitable for a flow-type reaction.

  A method for producing 1,1,1,4,4,4-hexafluoro-2-butyne by isomerization reaction of hexafluorocyclobutene is also known (Non-patent Document 2), but it is expensive and highly hygroscopic as a catalyst. In addition to using potassium fluoride, which is difficult to handle due to its properties, a yield of 89% is insufficient, and a method using a cheaper and more efficient catalyst is desirable.

  On the other hand, as one of the methods for producing hexafluorocyclobutene used as a raw material for 1,1,1,4,4,4-hexafluoro-2-butyne production, 1,2-dichloro-1,2,3, There is a reduction reaction of 3,4,4-hexafluorocyclobutane. In this method, it is common to react with zinc in an alcohol solvent in a batch system (Non-patent Document 3). Since processing of zinc chloride is required, there is a problem in manufacturing in large quantities.

  Production of hexafluorocyclobutene by dechlorination of 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane with hydrogen in the presence of metal oxide and / or silicon oxide Although the method to do is also known (patent document 1), the reaction rate and the selectivity are insufficient. A method of dechlorination in the presence of a phosphate catalyst is also known (Patent Document 2), but sufficient selectivity cannot be obtained. A method of dechlorination in the presence of a rhenium catalyst is also known (Patent Document 3), but it is necessary to use a large amount of expensive and rare rhenium as a supported amount of 5%.

Japanese Patent No. 3500707 US Pat. No. 3,636,173 International Publication No. 90/08748

V.A.Petro et.al, J. Fluorine Chem., 77 (1996) 139. R.D. Chambers, et.al, J. Fluorine Chem., 18 (1981) 407. G. Fuller, J.C.Tatlow, J. Chem. Soc., 3198 (1961).

  The present invention has been made in order to overcome the problems of the prior art as described above, and is suitable for a flow reaction formula and is an efficient hexafluorocyclobutene, and 1,1,1,4,4, The object is to provide a method for producing 4-hexafluoro-2-butyne.

  As a result of extensive research to achieve the above object, the present inventor has dechlorinated 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane with a catalyst to produce hexafluorocyclohexane. It was found that 1,1,1,4,4,4-hexafluoro-2-butyne can be produced efficiently by a flow-type catalytic reaction by using butene as a catalyst and then isomerizing with a catalyst.

The present invention has been completed based on these findings and provides the following inventions.
[1] A method for producing hexafluoro-2-butyne by isomerization of hexafluorocyclobutene, wherein sodium fluoride or a mixture containing sodium fluoride is used as an isomerization reaction catalyst. A process for producing hexafluoro-2-butyne characterized by carrying out isomerization.
[2] The production method of the above [1], wherein the step is carried out by a flow method.
[3] The production method of the above [1] or [2], wherein the isomerization reaction catalyst is in a pellet form.
[4] The production method of [1] or [2], wherein the carrier of the isomerization reaction catalyst is aluminum fluoride, calcium fluoride, zeolite, alumina, or activated carbon.
[5] The production method according to any one of claims 1 to 4, wherein the hexafluorocyclobutene is removed from 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane. A method for producing by chlorination, wherein at least one metal selected from nickel, copper, iron, cobalt, zinc, ruthenium, platinum, palladium and rhodium is used as a dechlorination catalyst. A method for producing butene.
[6] The production method of [5], wherein the dechlorination catalyst support is at least one selected from activated carbon, aluminum fluoride, alumina, and calcium fluoride. [7] The dechlorination The metal used as a catalyst is adjusted by reducing nickel chloride, copper chloride, iron chloride, cobalt chloride, zinc chloride, ruthenium chloride, hexafluoroplatinic acid, palladium chloride, or rhodium chloride with hydrogen. [5] and [6] production method.
[8] The production method of [5] to [7] above, wherein as the dechlorination catalyst, at least one selected from bismuth and thallium is mixed with at least one selected from palladium and rhodium.
[9] The production method of [5] to [8], wherein at least one of palladium and rhodium is pretreated with an aromatic amine as the dechlorination catalyst.
[10] The production method of the above-mentioned [9], wherein the aromatic amine is quinoline.

  According to the present invention, hexafluorocyclobutene and 1,1,1,4,4,4 are efficiently improved by a flow-type reaction method suitable for production on an industrial scale. -Hexafluoro-2-butyne can be produced.

In the present invention, 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane is dechlorinated with a catalyst to give hexafluorocyclobutene, followed by isomerization reaction with the catalyst. , 1,4,4,4-hexafluoro-2-butyne, wherein all steps are obtained by a flow-type catalytic reaction.
In the present invention, 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane can be produced by an existing method, but is preferably produced by a dimerization reaction of chlorotrifluoroethylene. it can.

  In the present invention, 1,1,1,4,4,4-hexafluoro-2-butyne is produced by dechlorination of 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane. Step to make hexafluorocyclobutene by (first step), Step to make 1,1,1,4,4,4-hexafluoro-2-butyne by isomerization of hexafluorocyclobutene (second step) May be performed in two steps, or the intermediate product hexafluorocyclobutene is purified by dechlorination of 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane. It may be performed in one continuous step without the subsequent isomerization reaction.

The step of producing hexafluorocyclobutene by dechlorination of 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane is performed by a flow reaction.
This dechlorination reaction is performed in the presence of a catalyst, and examples of the catalyst include nickel, copper, iron, cobalt, zinc, ruthenium, platinum, etc., preferably nickel, copper, and iron. An alloy containing a metal may be used, and an additive such as a metal salt may be further added. Catalysts such as palladium and rhodium are generally unsuitable because the hydrogenation reaction proceeds in addition to the dechlorination reaction. However, a catalyst in which palladium or rhodium is mixed with bismuth or thallium, or a catalyst in which palladium or rhodium is pretreated with an aromatic amine, preferably quinoline, suppresses the progress of the hydrogenation reaction and highly selects a dechlorinated product. It is preferable because it can be manufactured. A catalyst may be supported and used. Examples of such a carrier include activated carbon, aluminum fluoride, alumina, calcium fluoride, and the like, preferably activated carbon and aluminum fluoride. Further, the catalyst is supported on the carrier as a metal chloride such as nickel chloride, copper chloride (monovalent, divalent), iron chloride (divalent, trivalent), cobalt chloride, zinc chloride, ruthenium chloride, hexachloroplatinic acid, etc. Then, it is preferable to prepare by treating with hydrogen. Moreover, there is no problem even if the metal chloride is a hydrate.
The temperature of the reaction from 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane to hexafluorocyclobutene is usually 20 to 500 ° C., preferably 50 to 400 ° C.
The reaction may be carried out batchwise or flow-through.

  The process of producing 1,1,1,4,4,4-hexafluoro-2-butyne from hexafluorocyclobutene by isomerization can also be performed by flow reaction, but can also be performed by batch reaction. It is.

As a catalyst in the isomerization reaction, it is a feature of the present invention to use sodium fluoride which has a low hygroscopic property and can be easily handled in the atmosphere, and can obtain high activity and high selectivity. When sodium fluoride itself is used as a catalyst, it may be in powder form, but a pellet form is preferred for the flow reaction. In addition, it is possible to use sodium fluoride supported on a carrier such as alumina, porous aluminum fluoride, activated carbon, silica, or zeolite. It is also possible to use sodium fluoride in admixture with other components.
The temperature of the isomerization reaction is usually 200 to 800 ° C, preferably 400 to 600 ° C.

  By combining the above dechlorination reaction and isomerization reaction into a single continuous step, hexafluorocyclobutene is converted from 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane. It is also possible to produce 1,1,1,4,4,4-hexafluoro-2-butyne via it.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples.
[Example 1]
An aqueous solution of nickel (II) chloride hexahydrate was impregnated with activated carbon overnight and dried at 100 ° C. The amount of nickel chloride hexahydrate in the solution was adjusted so that the nickel loading was about 3% by weight. An inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with a catalyst of 100 mm in length, dried at 250 ° C., and then reduced at 250 ° C. for 6 hours in a hydrogen-nitrogen mixed gas flow at a flow rate of 40 ml / min.

  The reaction is performed by heating a reaction tube filled with the catalyst at a predetermined temperature and passing a predetermined amount of 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane, hydrogen, and nitrogen. Carried out. The reaction product was analyzed by gas chromatography, and the conversion rate of 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane and the yield of the desired hexafluorocyclobutene were corrected by a correction factor. Was calculated in consideration of The experimental results are shown in Table 1 below.

[Example 2]
An aqueous solution of nickel (II) chloride hexahydrate was impregnated with porous aluminum fluoride overnight and dried at 100 ° C. The amount of nickel chloride hexahydrate in the solution was adjusted so that the nickel loading was about 10% by weight. An inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with a catalyst of 100 mm in length, dried at 250 ° C., and then reduced at 250 ° C. for 6 hours in a hydrogen-nitrogen mixed gas flow at a flow rate of 40 ml / min.

  The reaction was carried out in the same manner as in Example 1 except that the above catalyst was used. The results are shown in Table 2.

[Example 3]
An aqueous solution of copper (II) chloride trihydrate was impregnated on activated carbon overnight and dried at 100 ° C. The amount of copper chloride trihydrate in the solution was adjusted so that the amount of copper supported was about 3% by weight. An inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with a catalyst of 100 mm in length, dried at 250 ° C., and then reduced at 250 ° C. for 6 hours in a hydrogen-nitrogen mixed gas flow at a flow rate of 40 ml / min.

  The reaction was carried out in the same manner as in Example 1 except that the above catalyst was used. The results are shown in Table 3.

[Example 4]
An aqueous iron (III) chloride solution was impregnated with activated carbon overnight and dried at 100 ° C. The amount of iron chloride in the solution (III was adjusted so that the amount of iron supported was about 3% by weight. An inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with a catalyst of 100 mm in length, and 250 ° C. And then reduced at 250 ° C. for 6 hours in a hydrogen-nitrogen mixed gas stream at a flow rate of 40 ml / min.

  The reaction was carried out in the same manner as in Example 1 except that the above catalyst was used. The results are shown in Table 4.

[Example 5]
An aqueous zinc chloride solution was impregnated in activated carbon overnight and dried at 100 ° C. The amount of zinc chloride in the solution was adjusted so that the amount of zinc supported was about 3% by weight. An inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with a catalyst of 100 mm in length, dried at 250 ° C., and then reduced at 250 ° C. for 6 hours in a hydrogen-nitrogen mixed gas flow at a flow rate of 40 ml / min.

  The reaction was carried out in the same manner as in Example 1 except that the above catalyst was used. The results are shown in Table 5.

[Example 6]
An aqueous solution of cobalt (II) chloride hexahydrate was impregnated with activated carbon overnight and dried at 100 ° C. The amount of cobalt chloride hexahydrate in the solution was adjusted so that the amount of cobalt supported was about 3% by weight. An inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with a catalyst of 100 mm in length, dried at 250 ° C., and then reduced at 250 ° C. for 6 hours in a hydrogen-nitrogen mixed gas flow at a flow rate of 40 ml / min.

  The reaction was carried out in the same manner as in Example 1 except that the above catalyst was used. The results are shown in Table 6.

[Example 7]
An aqueous solution of ruthenium (III) chloride hydrate was impregnated on activated carbon overnight and dried at 100 ° C. The amount of ruthenium chloride hydrate in the solution was adjusted so that the amount of ruthenium supported was about 0.5% by weight. An inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with a catalyst of 100 mm in length, dried at 250 ° C., and then reduced at 250 ° C. for 6 hours in a hydrogen-nitrogen mixed gas flow at a flow rate of 40 ml / min.

  The reaction was carried out in the same manner as in Example 1 except that the above catalyst was used. The results are shown in Table 7.

[Example 8]
An aqueous solution of hexachloroplatinic acid (IV) hexahydrate was impregnated on activated carbon overnight and dried at 100 ° C. The amount of hexachloroplatinic acid hexahydrate in the solution was adjusted so that the amount of platinum supported was about 0.5% by weight. An inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with a catalyst of 100 mm in length, dried at 250 ° C., and then reduced at 250 ° C. for 6 hours in a hydrogen-nitrogen mixed gas flow at a flow rate of 40 ml / min.

  The reaction was carried out in the same manner as in Example 1 except that the above catalyst was used. The results are shown in Table 8.

[Example 9]
An aqueous solution of nickel (II) chloride hexahydrate was impregnated with porous aluminum fluoride overnight and dried at 100 ° C. The amount of nickel chloride hexahydrate in the solution was adjusted so that the nickel loading was about 3% by weight. An inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with a catalyst of 100 mm in length, dried at 250 ° C., and then reduced at 250 ° C. for 6 hours in a hydrogen-nitrogen mixed gas flow at a flow rate of 40 ml / min.

  The reaction was carried out in the same manner as in Example 1 except that the above catalyst was used. The results are shown in Table 9.

[Example 10]
Activated carbon was impregnated with palladium chloride and an aqueous solution of thallium nitrate overnight and dried at 100 ° C. The amounts of palladium chloride and thallium nitrate in the solution were adjusted so that the supported amounts of palladium and thallium were about 0.5 wt% and about 1 wt%, respectively. An inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with a catalyst of 100 mm in length, dried at 250 ° C., and then reduced at 200 ° C. for 6 hours in a hydrogen-nitrogen mixed gas stream at a flow rate of 40 ml / min.

  The reaction was carried out in the same manner as in Example 1 except that the above catalyst was used. The results are shown in Table 10.

[Example 11]
Palladium chloride and an aqueous bismuth chloride solution were impregnated with activated carbon overnight and dried at 100 ° C. The amounts of palladium chloride and bismuth chloride in the solution were adjusted so that the supported amounts of palladium and bismuth were about 0.5 wt% and about 1 wt%, respectively. An inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with a catalyst of 100 mm in length, dried at 250 ° C., and then reduced at 200 ° C. for 6 hours in a hydrogen-nitrogen mixed gas stream at a flow rate of 40 ml / min.

  The reaction was carried out in the same manner as in Example 1 except that the above catalyst was used. The results are shown in Table 11.

[Example 12]
Rhodium chloride trihydrate and bismuth chloride aqueous solution were impregnated on activated carbon overnight and dried at 100 ° C. The amounts of rhodium chloride trihydrate and bismuth chloride in the solution were adjusted so that the supported amounts of rhodium and bismuth were about 0.5 wt% and about 1 wt%, respectively. An inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with a catalyst of 100 mm in length, dried at 250 ° C., and then reduced at 200 ° C. for 6 hours in a hydrogen-nitrogen mixed gas stream at a flow rate of 40 ml / min.

  The reaction was carried out in the same manner as in Example 1 except that the above catalyst was used. The results are shown in Table 12.

[Example 13]
An aqueous solution of palladium chloride was impregnated in activated carbon overnight and dried at 100 ° C. The amount of palladium chloride in the solution was adjusted so that the amount of palladium supported was about 0.5% by weight. An inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with a catalyst of 100 mm in length, dried at 250 ° C., and then reduced at 200 ° C. for 6 hours in a hydrogen-nitrogen mixed gas stream at a flow rate of 40 ml / min. Next, 2 ml of quinoline was dropped onto the reduced catalyst, the temperature was gradually raised from 50 ° C. to 300 ° C. under a nitrogen stream, and the catalyst was prepared by heat treatment at 300 ° C. for 2 hours.

  The reaction was carried out in the same manner as in Example 1 except that the above catalyst was used. The results are shown in Table 13.

[Example 14]
An Inconel reaction tube having a diameter of 11 mm and a length of 300 mm was filled with sodium fluoride pellets of 100 mm in length and dried at 250 ° C.
The reaction was carried out by heating the reaction tube at a predetermined temperature and passing a predetermined amount of hexafluorocyclobutene and nitrogen. The reaction product was analyzed by gas chromatography, and the conversion rate of hexafluorocyclobutene and the desired yield of 1,1,1,4,4,4-hexafluoro-2-butyne were taken into account in the correction factor. Calculated. The experimental results are shown in Table 14 below. Thereby, the result that it was excellent in the yield and the selectivity from the nonpatent literature 2 of a prior art was obtained.

Claims (10)

  A method for producing hexafluoro-2-butyne by isomerization reaction of hexafluorocyclobutene, characterized in that sodium fluoride or a mixture containing sodium fluoride is used as an isomerization reaction catalyst. -Method for producing butyne.   The manufacturing method according to claim 1, wherein the process is performed in a flow-through manner.   The production method according to claim 1 or 2, wherein the isomerization catalyst is in a pellet form.   The production method according to claim 1 or 2, wherein the carrier of the isomerization reaction catalyst is aluminum fluoride, calcium fluoride, zeolite, alumina, or activated carbon.   The production method according to any one of claims 1 to 4, wherein the hexafluorocyclobutene is obtained by dechlorination of 1,2-dichloro-1,2,3,3,4,4-hexafluorocyclobutane. A method for producing hexafluorocyclobutene, characterized in that at least one metal selected from nickel, copper, iron, cobalt, zinc, ruthenium, platinum, palladium and rhodium is used as a dechlorination catalyst. Method.   6. The production method according to claim 5, wherein the carrier of the dechlorination catalyst is at least one selected from activated carbon, aluminum fluoride, alumina, and calcium fluoride.   The metal used as the dechlorination catalyst is adjusted by hydrogen reduction of nickel chloride, copper chloride, iron chloride, cobalt chloride, zinc chloride, ruthenium chloride, hexafluoroplatinic acid, palladium chloride, or rhodium chloride. The manufacturing method of Claim 5 or Claim 6.   The production method according to claim 5, wherein at least one selected from bismuth and thallium is mixed with at least one of palladium and rhodium as the dechlorination catalyst.   The production method according to claim 5, wherein at least one of palladium and rhodium is pretreated with an aromatic amine as the dechlorination catalyst.   The method according to claim 9, wherein the aromatic amine is quinoline.