Central Glass Company, Limited

Yutaka Katsuhara

Toshihiro Nakamichi

Toshikazu Kawai

Toru Nakazora

Yoshihiro Tasaka

Satoru Narizuka

Takashi Kume

Michio Ishida

Koshi Okazaki

Shinya Akiba

Ryo Nadano

Mineo Watanabe

Makoto Koide

Hiroshi Takahashi

Kimiaki Matsuoka

Tatsuya Hayasaka

Fumio Inoue

Yoshiaki Miyamoto

Tuneyoshi Hisayuki

Katumi Takesita

Takeshi Kondow

Mithio Sawai

There is provided according to the present invention a process for producing fluoromethyl hexafluoroisopropyl ether ((CF)CH&#x2014;O&#x2014;CHF), including: reacting bisfluoromethyl ether with hexafluoroisopropyl alcohol in a solvent substantially immiscible with hydrogen fluoride in the presence of a catalytic amount of a strong acid selected from sulfuric acid and any other acids stronger in acidity than sulfuric acid. The process of the present invention enables industrial production of the fluoromethyl hexafluoroisopropyl ether without using hydrogen fluoride or a large amount of sulfuric acid and thereby without causing a large amount of waste as a by-product.

Process for producing fluoromethyl hexafluoroisopropyl ether

According to the present invention, an &#x3b1;-substituted acrylic ester monomer for a fluorinated resist is produced by direct addition of an &#x3b1;-substituted acrylic acid to a fluorinated alkene in the presence of a specific acid catalyst having a sulfonyl group. By the use of such a specific acid catalyst, it is possible to achieve industrial-scale production of the &#x3b1;-substituted acrylic ester monomer for the fluorinated resist by carrying out the target addition reaction of the fluorinated alkene and the &#x3b1;-substituted acrylic acid efficiently during the occurrence of side reactions such as isomerization of the alkene, generation of a diol and excessive addition of the &#x3b1;-substituted acrylic acid.

Process for producing monomer for fluorinated resist

To provide a process for producing anhydrous hexafluoroacetone from hexafluoroacetone hydrate. To provide a process taking environment into consideration, that does not require a treatment of wastes, such as waste sulfuric acid, containing organic substances, which is inevitable in processes conducted hitherto using concentrated sulfuric acid, fuming sulfuric acid, and the like. A process for dehydrating a hexafluoroacetone hydrate, comprising introducing a hexafluoroacetone hydrate and hydrogen fluoride either as a mixture or separately into a distillation column, obtaining a composition containing hexafluoroacetone or a hexafluoroacetone-hydrogen fluoride adduct and hydrogen fluoride as a low boiling component, and obtaining a composition containing water and hydrogen fluoride as a high boiling component.

Process for dehydration of hexafluoroacetone hydrate

The present invention relates to a process for producing a trifluoromethylbenzylamine represented by the general formula (1). This process includes the step of reducing an oxime represented by the general formula (2),

Process for producing trifluoromethylbenzylamines

The invention relates to a method for producing a bis(trifluoromethyl)benzene. This method includes the steps of (a) chlorinating a compound represented by the general formula (1) by chlorine, thereby to produce a trichloromethyltrifluoromethylbenzene; and (b) fluorinating the tricbloromethyltrifluoromethylbenzene by hydrogen fluoride, thereby to produce the bis(trifluoromethyl)benzene, ##STR1## where m is 1, 2 or 3. It is not necessary in the invention to handle solid in any reaction step. Therefore, the invention is very useful in the production of a bis(trifluoromethyl)benzene in an industrial scale

Method for producing bis (trifluoromethyl) benzene

A method for removing a perfluoroalkyl alcohol from a waste gas and recovering the perfluoroalkyl alcohol comprising the steps of bringing the waste gas into contact with an aqueous alkaline solution thereby to absorb the perfluoroalkyl alcohol into said solution and consequently obtain an aqueous alkaline solution containing an alkoxide of the perfluoroalkyl alcohol. Adding an acid to the aqueous alkaline solution containing the alkoxide of the perfluoroalkyl alcohol until the alkaline solution turns into an acidic solution with a pH value smaller than 5, thereby to turn said alkoxide into said perfluoroalkyl alcohol and subjecting the acidic solution to distillation to recover the perfluoroalkyl alcohol.

Method for removing and recovering fluorinated alcohol from waste gas

In the preparation of m-chlorobenzotrifluoride (m-CBTF) by reaction between benzotrifluoride and chlorine gas, a combination of a chloride of a metal having a valence of 3 to 6 and a small amount of iodine is used as catalyst. Alternative to iodine use can be made of an iodide that liberates iodine in the presence of chlorine. The catalyst exhibits high selectivity for m-CBTF and is effective for increasing the ratio of m-CBTF to p-CBTF in the reaction product.

Process of preparing metachlorobenzotrifluoride

1,1,1,3,3,3-hexafluoropropane-2-ol is prepared easily and efficiently by gas-liquid reaction between hydrogen gas and a hexafluoroacetone hydrate such as trihydrate, which is liquid at room temperature, using a suitable catalyst such as active carbon-palladium catalyst. Preferably the gauge pressure of hydrogen gas is 2-10 kg/cm.sup.2, and the hydrogenolysis reaction temperature is 70.degree.-100.degree. C. The life of the catalyst can be prolonged by the addition of a small quantity of sodium hydroxide. The addition of a small quantity of aluminum hydroxide is effective in suppressing the formation of fluorine ions in the reaction liquid.

Preparation of 1,1,1,3,3,3-hexafluoropropane-2-ol by hydrogenolysis of

Dehydrating decomposition of compound (I), i.e. gem-diol, hemi-acetal or hemi-ketal, by contact with sulfuric acid gives a carbonyl compound (II). ##STR1## Disclosed is a two-stage process in which the first stage is the contact of compound (I) with sulfuric acid at 90.degree.-140.degree. C. so as to partly decompose and dehydrate the compound (I), permitting the concentration of sulfuric acid to become lower than 93 wt. % but not lower than 65 wt. %, and the second stage is the contact of the product of the first-stage reaction with concentrated sulfuric acid at a temperature not higher than 60.degree. C., preventing the concentration of sulfuric acid from becoming lower than 93 wt %. For example, hexafluoroacetone is obtained from a hydrate thereof by this process using only a small amount of sulfuric acid.

Dehydrating decomposition process for preparing carbonyl compound

Crude hexafluoroacetone (HFA) hydrate containing chlorofluoroacetone(s) hydrate(s) as impurity is purified by adding an alkali metal hydroxide and maintaining at an elevated temperature, preferably at 100.degree.-110.degree. C., to thereby cause decomposition reaction of every chlorofluoroacetone hydrate with the alkali metal hydroxide, followed by neutralization of an excess portion of the alkali metal hydroxide. Alkali metal hydroxides, which readily react with anhydrous HFA, react preferentially with chlorofluoroacetone hydrates but hardly react with coexisting HFA hydrate.

Method of purifying hexafluoroacetone hydrate

Vapor phase contact reaction between water and benzal chloride or a substitute expressed by C.sub.6 H.sub.(5-n) X.sub.n CHCl.sub.2, wherein X representing a halogen atom or a trifluoromethyl group and n being 1 or 2, to form benzaldehyde or a substitute expressed by C.sub.6 H.sub.(5-n) X.sub.n CHO can efficiently be achieved by using activated carbon treated with an acid such as sulfuric acid or impregnated with a metal chloride such as ferric chloride and/or a metal sulfate such as cupric sulfate as catalyst. The activated carbon catalyst long retains its high activity even when the starting material has trifluoromethyl group, which is liable to undergo partial decomposition with formation of hydrogen fluoride.

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Kawagoe, Japan

Yutaka Katsuhara