GB859342A - 2-phenylbenzamide derivatives - Google Patents

Abstract

The invention comprises compounds of the formula : <FORM:0859342/IV(b)/1> (wherein R is hydrogen or carbamoyl or a hydrocarbon or alkanoyl radical, X is hydrogen or cyano or one or more halogen atoms and Y is hydrogen or one or more halogen atoms) but excluding unsubstituted 2-phenyl-benzamide and 2-(p-chlorophenyl)-benzamide; and their preparation (1) by reacting the appropriate 2-phenylbenzoyl halides or alkyl 2-phenyl-benzoate with the amino compound RNH2; (2) for compounds wherein R is hydrogen and X is not cyano, hydrolysing an appropriate 2-phenylbenzonitrile; (3) for compounds wherein R is hydrogen, heating an appropriate ammonium 2-phenyl-benzoate; and (4) for compounds wherein R is alkanoyl, by arylation of the compounds wherein R is hydrogen. Examples are given, R being various lower alkyl, lower alkenyl, aralkyl and lower alkanoyl radicals or hydrogen, X being variously o-I, -bl, -Br and -CN, p-Br, -bl and -F, n-bl and 2 : 5-dibl and Y being variously 5-Br, -bl and -F and 4-bl. 2-Phenyl-benzoyl chloride is prepared from the acid and phosphorous pentachloride. 2-(p-chloro-phenyl)-5-chloro-benzoyl chloride is prepared from the acid and thionyl chloride. 2-(p-Chlorophenyl)-5-chloro-benzoic acid is prepared either by heating 2 : 7-dichlorofluorenone with potassium hydroxide in water at 220 DEG C.; or by diazotizing 2-(p-chlorophenyl)-5-chloroaniline and then reacting with cuprous cyanide to give 2-(p-chlorophenyl)-5-chloro-benzonitrile and then refluxing this with sodium hydroxide and ethanol. 2-(p-Fluorophenyl)5-fluoro-benzoic acid and 2-(p-fluorophenyl)-benzonitrile are prepared by similar methods, the first via 2-(p-fluorophenyl)-5-fluoro-benzonitrile. 2-(p-Bromophenyl)-5-chlorobenzoic acid is prepared by bromination of 2-phenyl-5-chloro benzoic acid. 2-(p-Bromophenyl)-benzoic acid is prepared similarly. 2-(p-chlorophenyl)-5-bromobenzoic acid is prepared by chlorinating methyl 2-phenyl-5-bromobenzoate to give methyl 2-(p-chlorophenyl)-5-bromo-benzoate and hydrolysing this with sodium hydroxide. 2-(21:51-Dichlorophenyl)-benzoic acid is prepared by condensing 2 : 5-dichloro-iodobenzene with methyl o-iodobenzoate in presence of copper bronze at 260 DEG C. and hydrolysing the methyl 2-(21 : 51-dichlorophenyl)-benzoate soproduced. 2-(o-chlorophenyl)-5-bromobenzoic acid is prepared similarly. 2-Phenyl-5-fluoro-benzoic acid is prepared by reducing methyl 2-phenyl-5-nitro-benzoate to give methyl 2-phenyl-5-amino-benzoate, diazotizing this and reacting with sodium borofluoride to give methyl 2-phenyl benzoate 5-diazonium borofluoride, heating this and hydrolysing the steam-distilled residue. 2-(p-Iodophenyl)-benzoic acid is prepared by heating 2-iodofluorenone with potassium hydroxide in diphenyl ether at 180 DEG C. The Provisional Specification describes new compounds of the formula: <FORM:0859342/IV(b)/2> wherein R is hydrogen or a hydrocarbon or acyl radical and wherein the benzene ring may optionally contain additional substituents, such as halogen atoms and lower alkyl and lower alkoxy radicals.