Patent GB-1499508-A (GB)
Title: 3,3,3-trifluoropropionic acid derivatives
IPC: C07C41/16
Filed: 1974-12-06
Abstract: 1499508 3,3,3-Trifluoropropionic acid derivatives IMPERIAL CHEMICAL INDUSTRIES Ltd 5 Nov 1975 [6 Dec 1974] 52829/74 Heading C2C The invention comprises 3,3,3-trifluoropropionic acid derivatives of the formula wherein Ar is phenyl or naphthyl optionally substituted by halogen, C 1-4  alkyl, C 1-4  alkoxy, or phenyl or phenoxy optionally substituted by halogen C 1-4  alkyl or C 1-4  alkoxy; X is or CH 2  or a valence bond; R<SP>1</SP> is hydroxy, amino, dimethylamino or C 1-6  alkoxy optionally substituted by carbamoyl, dialkyl carbamoyl or dialkylamino or by a pyridyl, halophenoxy or by a radical of the formula and R<SP>2</SP> is H or C 1-4  alkyl or CF 3  and for these compounds wherein R<SP>1</SP> is OH, the pharmaceutically acceptable salts thereof and their preparation by (a) reacting compounds of the formula where X is other than a valence bond, Z is halogen, alkene- or arene-sulphonyloxy, and when X is a valence bond, 2 is aryliodonium or 2-thienyl-iodonium, with salts of the formula wherein M<SP>+</SP> is a metal cation; (b) for compounds in which R<SP>1</SP> is OH, hydrolysing the corresponding C 1-6  alkyl esters; (c) for compounds in which R<SP>1</SP> is NH 2 , hydrolysing the corresponding nitriles; (d) for compounds in which R<SP>1</SP> is NH 2  or N(CH 3 ) 2 , reacting the corresponding acid halides with ammonia or dimethylamine (e) for compound in which R<SP>1</SP> is an optionally substituted alkoxy group, esterifying the corresponding acids; (f) for compounds in which R<SP>1</SP> is N(CH 3 ) 2  and R<SP>2</SP> is H, heating compounds of the formula with dimethylformamide and sodium hydride; and (g) for compounds wherein R<SP>2</SP> is other than CF 3 , in optically active forms, resolving the corresponding racemic compound or carrying out one of the above processes using optically active starting materials. Acid chlorides of the formula are obtained by reacting the corresponding acids with thionyl chloride. Ethyl 2 - hydroxy - 3,3,3 - trifluoro - 2 - trifluoromethylpropionate is obtained by esterifying the corresponding acid, resulting from the hydrolysis of 2-hydroxy-3,3,3-trifluoro-2-trifluoromethylpropionitrile sodium salt. 2 - (4 - Chlorobenzyloxy) - 3,3,3 - trifluoro- 2 - trifluoromethylpropionitrile is prepared by reacting 2 - hydroxy - 3,3,3 - trifluoro - 2- trifluoromethylpropionitrile sodium salt with 4-chlorobenzyl chloride. 2 - Chloromethyl - 6 - chloronaphthalene is prepared by reacting thionyl chloride with 6- chloro - 2 - hydroxymethylnaphthalene, resulting from the reduction of methyl 6-chloro-2-naphthoate, which is made by esterifying 6-chloro-2- naphthoic acid, obtained by treating 2-acetyl- 6-chloronaphthalene with sodium hypochlorite. 2 - [4 - (4 - Chlorophenyl)benzyloxy] - 3,3,3- trifluoro - 2 - trifluoromethylpropionitrile is obtained by reacting 2-hydroxy-3,3,3-trifluoro- 2 - trifluoromethylpropionitrile sodium salt with 4-(4-chlorophenyl)benzyl chloride. 4 - [4 - (4 - Chlorophenyl)phenoxymethyl chloride is prepared by reacting phosphorus pentachloride with sodium 4-(4-chlorophenyl)- phenoxymethylsulphonate, resulting from the reaction between 4-(4-chlorophenyl)phenol and sodium chloromethylsulphonate. 4 - Bi - phenyl - 2 - thienyliodonium chloride is obtained by reacting (diacetoxy iodo)-4- biphenyl and thiophene in the presence of acetic anhydride and trifluoroacetic acid. 4 - (4 - Chlorophenyl)phenyl - 2 - thienyliodonium trifluoroacetate is prepared by reacting thiophene and 4 - (4 - chlorophenyl) - (diacetoxyiodo)benzene, obtained by acetylating 4-(4- chlorophenyl)iodobenzene. () - Methyl - 2 - hydroxy - 3,3,3 - trifluoropropionate is obtained by esterifying the corresponding acid. 2 - Chloromethyl - 6 - methoxynaphthalene is obtained by reacting thionyl chloride with 2- hydroxymethyl-6-methoxynaphthalene, resulting from the reduction of methyl 6-methoxy-2- naphthoate.