Occidental Chemical Corporation

Gabriel Performance Products, LLC

Lawrence B Fertel

Henry C Lin

William S Derwin

Neil J O'Reilly

Ramesh Krishnamurti

Jeffrey S Stults

Michael J Fifolt

James J Maul

Mary K Cocoman

Walter M Opalinski

Viktor D Sorokin

Mahendra K Dosi

Bao-Guo Huang

A 2-bromo-4-chloro substituted phenol is prepared from a first composition of a substituted phenol and benzotrifluoride in a weight ratio to the substituted phenol of about 2 to about 4. Into the first composition is sparged about 1 to about 1.5 equivalents of chlorine gas, whereby the substituted phenol is chlorinated to form a 4-chloro substituted phenol. The first composition is cooled to precipitate the 4-chloro substituted phenol, which can be isolated by filtration. A second composition is formed of the 4-chloro substituted phenol, acetic acid in an weight ratio to the 4-chloro substituted phenol of about 1 to about 2, about 1 to about 2 equivalents of a salt of a strong base and a weak acid, and about 1 to about 5 equivalents of a brominating agent, whereby the 4-chloro substituted phenol is brominated to form a 2-bromo-4-chloro substituted phenol.

Method of making 2-bromo-4-chloro substituted phenols

Disclosed is a composition of (1) a substituted benzaldehyde having the general formula ##STR1## where X is a leaving group in the ortho or para position, (2) a mercaptide having the general formula MSR' in an amount about stoichiometric to about 20 mole % in excess of stoichiometric with the amount of said substituted benzaldehyde, where M is an alkali metal and R' is alkyl or haloalkyl from C.sub.1 to C.sub.8 or aryl, aralkyl, or alkyl from C.sub.6 to C.sub.12, (3) sufficient water to dissolve said mercaptide and MX, (4) about 0.1 to about 5 mole %, based on said substituted benzaldehyde, of a phase transfer catalyst, and (5) 0 to about 100 wt %, based on total composition weight, of a water-immiscible organic solvent. Heating the composition to a temperature between about room temperature and 100.degree. C. results in the formation of a substituted mercapto-benzaldehyde.

Synthesis of substituted mercapto-benzaldehydes

Disclosed is a method of making trichloromethoxybenzene. A mixture is prepared of anisole and a source of chlorine free radicals, such as chlorine or sulfuryl chloride. The reaction is performed in a solvent, which can be either benzotrifluoride, orthochlorobenzotrifluoride, metachlorobenzotrifluoride, parachlorobenzotrifluoride, or dichlorobenzotrifluoride. The mixture is exposed to actinic radiation, such as ultraviolet light, which generates the chlorine free radicals.

Method of making trichloromethoxybenzene

Disclosed are novel compounds having the formula ##STR1## where A is O or NR, each R' independently selected from hydrogen, R, or M, R is alkyl, aryl, alkaryl, or aralkyl from C.sub.1 to C.sub.12, and M is a cation. Also disclosed is a method of making those compounds and a method of making a mixture of 3,5-difluorobenzoic acid and 1,3-difluorobenzene by reacting 3,5-dichlorophthalic anhydride with a fluorinating agent to produce 3,5-difluorophthalic anhydride, reacting the 3,5-difluorophthalic anhydride with water to produce 3,5-difluorophthalic acid, and decarboxylating the 3,5-difluorophthalic acid.

Difluorophthalic compounds and their preparation

Disclosed is a method of making 3-methoxy-2,4,5-trifluorobenzoic acid. A tetrafluorophthalimide is reacted with an alkali metal hydroxide to produce a mixture of alkali metal salts of 4-hydroxy-3,5,6-trifluoro-N-alkylphthalamic acid and 3-hydroxy-2,4,5-trifluoro-N-alkylbenzamide. Those products are reacted with a methylating agent to produce 4-methoxy-3,5,6-trifluoro-N-alkylphthalamic acid and 3-methoxy-2,4,5-trifluoro-N-alkylbenzamide. Those products are reacted with an acid to produce 4-methoxy-3,5,6-trifluorophthalic acid and 3-methoxy-2,4,5-trifluorobenzoic acid. Finally, the 4-methoxy-3,5,6-trifluorophthalic acid is reacted with a decarboxylating agent to produce additional 3-methoxy-2,4,5-trifluorobenzoic acid.

Method of making 3-methoxy-2,4,5-trifluorobenzoic acid

A process for the selective hydrodefluorination of a tetrafluorophthalimide compound of the formula ##STR1## where X is 1 and R is a monovalent organo group; or X is 2 and R is a divalent organo group; comprises reacting (I) the tetrafluorophthalimide with zinc in an aqueous alkali metal hydroxide medium. The product may be hydrolyzed to form 3,4,6-trifluorophthalic acid.

Process for selective hydrodefluorination

Disclosed is a method of making 3-hydroxy-2,4,5-trifluorobenzoic acid. A aqueous solution is prepared of an alkali metal base and a tetrafluorophthalimide. The solution is heated to produce a mixture of a salt of a 4-hydroxy-3,5,6-trifluorophthalamic acid and a salt of a 3-hydroxy-2,4,5-trifluorobenzamide. The solution is neutralized with acid to form a precipitate of the 4-hydroxy-3,5,6-trifluorophthalamic acid and the 3-hydroxy-2,4,5-trifluorobenzamide. The precipitate is reacted with a mineral acid to produce 3-hydroxy-2,4,5-trifluorobenzoic acid.

Method of making 3-hydroxy-2,4,5-trifluorobenzoic acid

3,5-Diaminobenzotrifluoride can be produced, in a single step, by reacting 4-chloro-3,5-dinitro benzotrifluoride in a suitable solvent, with hydrogen gas, in the presence of a catalyst comprising palladium on a suitable carrier, and in the presence of a suitable base.

Preparation of 3,5-diamino benzotrifluoride

Plychlorophthalimides, specifically, N-substituted tetrachlorophthalimides and N-substituted trichlorophthalimides may be treated with zinc and a base in aqueous soluction to yield, after acidification, the product 3,5-dichlorophthalic acid or salts thereof.

Preparation of 3,5-dichlorophthalic acid and 3,5-dichlorophthalic

Polyfluorobenzenes are prepared by the decarboxylation of polyfluorophthalic acids or polyfluorobenzoic acids, in the presence of a Cu, CuO or Cu.sub.2 O catalyst in either quinoline or N-methyl-2-pyrrolidone as a solvent.

Preparation of fluorobenzenes by the decarboxylation of fluorophthalic

A process for the aromatization of 4-chlorotetrahydrophthalic anhydride and 4,5-dichlorotetrahydrophthalic anhydride which comprises heating a solution of either substance in the presence of activated carbon and in the partial absence of air.

Preparation of halogenated phthalic anhydrides

2-Chloro-4,5-difluorobenzoic acid may be prepared by decarboxylating 4,5-difluorophthalic anhydride or 4,5-difluorophthalic acid by heating in N-methyl-2-pyrrolidone or dimethyl acetamide optionally using copper, copper oxide, copper salts, or halides or salts of Zn, Cd, Ag and Ni as a catalyst to form 3,4-difluorobenzoic acid, reacting said 3,4-difluorobenzoic acid with a mixture of nitric and sulfuric acids to form 2-nitro-4,5-difluorobenzoic acid, reacting said 2-nitro-4,5-difluorobenzoic acid with elemental chlorine at a temperature of between 185.degree. and 195.degree. C. to form 2-chloro-4,5-difluorobenzoic acid.

Preparation of 2-choloro-4,5-difluorobenzoic acid from

4,5-Difluoroanthranilic acid may be prepared by decarboxylating 4,5-difluorophthalic anhydride or 4,5-difluorophthalic acid by heating in dimethyl acetamide, N-methyl-2-pyrrolidone or quinoline, optionally by reaction with copper, copper oxide, copper salts, or halides and salts of Zn, Cd, Ag and Ni as a catalyst, whereby 3,4-difluorobenzoic acid is formed; nitrating said 3,4-difluorobenzoic acid in a mixture of nitric and sulfuric acids to form 2-nitro-4,5-difluorobenzoic acid, and reducing said 2-nitro-4,5-difluorobenzoic acid to form 4,5-difluoroanthranilic acid.

Process for the preparation of 4,5-difluoroanthranilic acid from

Disclosed is a method of making ionized fluoroanthranilic acid from a fluorophthalic compound in a single pot process without isolating any intermediate product. A composition is prepared which comprises an aqueous solution of water, a fluorophthalic compound selected from the group consisting of ##STR1## and mixtures thereof, where 'n' is 1 to 4, at a concentration of about 5 to about 30 percent by weight based on the water weight, and about 1 to about 1.5 equivalents of hydroxylamine or a mineral acid salt thereof. The pH of the composition is maintained at at least about 11 and the temperature of the composition is maintained at at least about 90.degree. C. The unionized form of the acid is made by cooling below 50.degree. C. and lowering the pH to between about 4 and about 5. Also disclosed are the intermediate compounds, fluoro-N-hydroxyphthalimides, and a method of making them.

Single pot process for making a fluoroanthranilic acid

4,5-Difluorphthalic anhydride and 4,5-difluorophthalic acid may be decarboxylated in high yield to 3,4-difluorobenzoic acid by heating in N-methyl-2-pyrrolidone or dimethyl acetamide using copper, copper oxide, copper salts, or halides and salts of Zn, Cd, Ag and Ni as a catalyst.

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Williamsville, NY, United States of America

Lawrence B Fertel