Central Glass Company, Limited

Yoshihiko Gotoh

Fuyuhiko Sakyu

Yasuo Hibino

Satoshi Yoshikawa

Ryouichi Tamai

Toshikazu Kawai

Junji Negishi

Yasunori Nishimura

The present invention relates to a method for producing 1,1,1,3,3-pentafluoropropane. This method includes a first step of fluorinating 1-chloro-3,3,3-trifluoropropene in a liquid phase by hydrogen fluoride in the presence of an antimony compound as a catalyst, or a second step of fluorinating 1-chloro-3,3,3-trifluoropropene in a gas phase by hydrogen fluoride in the presence of a fluorination catalyst. If the first step is taken, 1,1,1,3,3-pentafluoropropane can be produced with a high yield. If the second step is taken, 1,1,1,3,3-pentafluoropropane can continuously be easily produced. Therefore, the second step is useful for an industrial scale production thereof. According to the invention, 1-chloro-3,3,3-trifluoropropene may be produced by a method including a step of reacting 1,1,1,3,3-pentachloropropane with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst. This method is useful, because yield of 1-chloro-3,3,3-trifluoropropene is high.

Method for producing 1,1,1,3,3-pentafluoropropane

The present invention relates to a method for producing 1,1,1,3,3-pentafluoropropane. This method includes the steps of (a) adding hydrogen fluoride to 1-chloro-3,3,3-trifluoropropene in the presence of an addition catalyst to obtain 1,1,1,3-tetrafluoro-3-chloropropane; and (b) disproportionating the 1,1,1,3-tetrafluoro-3-chloropropane into the 1,1,1,3,3-pentafluoropropane and 1,1,1-trifluoro-3,3-dichloropropane, in the presence of a disproportionation catalyst. This method is a useful method for producing 1,1,1,3,3-pentafluoropropane in an industrial scale, because its steps (a) and (b) are respectively superior in selectivity and yield. According to the invention, 1-chloro-3,3,3-trifluoropropene may be produced by a method including a step of reacting 1,1,1,3,3-pentachloropropane with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst. This method is useful, because yield of 1-chloro-3,3,3-trifluoropropene is high.

The present invention relates to a method for producing 1,1,1,3,3-pentafluoropropane. This method includes a step of adding hydrogen fluoride to 1,3,3,3-tetrafluoropropene in a liquid phase in the presence of a hydrohalogenation catalyst. This method is a useful method for producing 1,1,1,3,3-pentafluoropropane in an industrial scale, because yield of 1,1,1,3,3-pentafluoropropane is high. According to the invention, 1,3,3,3-tetrafluoropropene may be produced by a method including a step of reacting 1,1,1,3,3-pentachloropropane with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst, or by another method including a step of reacting 1-chloro-3,3,3-trifluoropropene with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst. According to the invention, 1-chloro-3,3,3-trifluoropropene may be produced by a method including a step of reacting 1,1,1,3,3-pentachloropropane with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst.

Method for producing 1,1,1,3,3,-pentafluoropropane

The invention provides a process for easily, efficiently and economically preparing bis(trifluoromethylphenyl)methanol from either toluoyl chloride or a trihalomethylbenzoyl chloride. First the starting compound is reacted with toluene in the presence of a strong acid catalyst such as a perfluoroalkylsulfonic acid to form a benzophenone derivative, CX.sub.3 C.sub.6 H.sub.4 --CO--C.sub.6 H.sub.4 CH.sub.3, wherein X is H, F, Cl or Br. Next, by chlorination the benzophenone derivative is converted into CY.sub.3 C.sub.6 H.sub.4 --CO--C.sub.6 H.sub.4 CCL.sub.3, wherein Y is F or Cl, and then the chlorinated intermediate is fluorinated into bis(trifluoromethyl)benzophenone. By reduction of carbonyl group of this benzophenone derivative the aimed compound is obtained.

Process of preparing bis (trifluoromethylphenyl) methanol

Trifluoromethylbenzoic acid is obtained at high yield from .alpha.,.alpha.,.alpha.,.alpha.',.alpha.',.alpha.'-hexafluoroxylene, which is a relatively inexpensive compound, by reacting this compound with a strong acid in sulfuric acid which is at least partly fuming sulfuric acid. It is best to use fuming sulfuric acid as the strong acid. The reaction temperature ranges from room temperature to 150.degree. C., though temperatures below 100.degree. C. are preferable. By this reaction only one trifluoromethyl group of hexafluoroxylene is hydrolyzed so far as the strong acid is not in large excess.

Preparation of trifluoromethylbenzoic acid from hexafluoroxylene

An isomer mixture of 4-trifluoromethyl-2-nitrobenzoic acid and 4-trifluoromethyl-3-nitrobenzoic acid, which is a novel compound, is obtained by nitrating a compound represented by ##STR1## (Z is COY or CY.sub.3, and Y is a halogen atom) with a nitrating agent comprising nitric acid and simultaneously hydrolyzing the radical Z. Each of the two isomers is easily isolated by treating the mixture with a basic neutralizing agent to obtain a solution containing the 2-nitro isomer and a precipitate containing the 3-nitro isomer.

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Miyoshi, Japan

Yoshihiko Gotoh