Patent GB-893072-A (GB)
Title: Benzophenone sulphonamides and process for producing same
IPC: C07D209/48
Filed: 1958-10-30
Abstract: The invention comprises compounds of the formula <FORM:0893072/IV (b)/1> or <FORM:0893072/IV (b)/2> wherein R1 is a halogen atom, e.g. Cl, Br or F, or an amino or C1-4 alkyl or alkoxy group, R2 is hydrogen or a halogen atom, or a C1-4 alkyl or alkoxy group, a carboxyl, carbalkoxy, carbamylalkoxy or sulphamyl group, or a carbamylalkoxy or sulphamyl group substituted by C1-4 alkyl, alkenyl or hydroxyalkyl groups or by a 3-oxapentylene-(1 : 5) radical, or a carboxyalkoxy group, or a carbamyl group substituted by a polymethylene or 3-oxapentylene-(1 : 5) radical or by two C1-4 alkyl, alkenyl or hydroxyalkyl radicals, or, except in the position ortho to the carbonyl group, a carbamyl group optionally bearing C1-4 alkyl, alkylene or hydroxyalkyl sibstituents, R3 corresponds to the definition of R2 and may also be an amino, alkanoylamino, nitro or hydroxyl group, R4 is hydrogen, halogen or C1-4 alkyl or alkoxy, R5 is halogen or C1-4 alkyl or alkoxy, R6 is hydrogen or C1-4 alkyl, alkenyl or hydroxyalkyl, R7 is hydrogen, halogen, C1-4 alkyl or alkoxy, carbalkoxy, a carbamyl, carbamylalkoxy or sulphamyl group optionally bearing C1-4 alkyl, alkenyl or hydroxyalkyl substituents or a polymethylene or 3-oxapentylene-1 : 5-substituent or is an alkanoylamino, nitro or hydroxyl group.  It comprises also the preparation of these compounds by (a) reacting a benzophenonesulphonyl halide or a benzophenone-sulphonic ester corresponding to the sulphonamides of formula Ia, or an isoindoline sulphohalide or sulphonic ester corresponding to the sulphonamide Ib, or a halogen lactone sulphohalide or sulphonic ester <FORM:0893072/IV (b)/3> (X=Cl, Br or alkoxy) with ammonia or (b) oxidising a corresponding diphenyl methane or 3-aminosulphenyl-diphenyl methane or -benzophenone compound or a 3-(m-aminosulphenylphenyl) isoindoline compound to replace the -CH2- and/or -SNH2 groups by -CO- and/or SO2NH2 groups as required to give the desired products.  Other methods of preparation whereby one substituent group is converted into another, e.g. acylation of an amino group or conversions of an amino group via the diazonium salts are described.  The halogen lactone sulphohalide IIc above wherein X is a halogen atom is suitably prepared by reacting a benzophenone o-carboxylic acid m1-sulphohalide, sulphonic acid or sulphonic ester with an inorganic acid halide such as thionyl chloride.  Examples describe the preparation of 4-chloro-benzophenone-3 : 41-disulphonamide, 4-chloro-21-carboxy - benzophenone - 3 - sulphonamide, 4 - methyl - benzophenone - 3 : 41 - disulphon - amide, 1 - oxo - 3 - (31 - sulphamoyl - 41 - chlorophenyl) - 3 - hydroxy - isoindoline, 4 - chloro - 31 - amino (and acetylamino) - benzo - phenone - 3 - sulphonamide, 4 - chloro - 31 - hydroxy - benzophenone - 3 - sulphonamide, 4 - chloro - benzophenone - 3 : 31 - disulphonamide, 4 - chloro - 41 - carboxy - benzophenone - 3 - sulphonamide, 4 - chloro - 21 - carboxy - benzo - phenone - 3 - sulphonamide, 3 - chloro - 21 - diethylcarbamoyl - benzophenone - 3 - sulphon - amide and many others.  Sulphonic acid derivatives used as starting materials corresponding to the products of formula Ia but containing, in place of the sulphonamide group and possibly also in place of R2, a sulphonic acid, sulphonic ester or sulphohalide group are prepared by standard methods such as by sulphonating and reacting the resulting sulphonic acid, e.g. 4-chloro-31-nitro-benzophenone-3-sulphonic acid, with an inorganic acid halide such as phosphorus oxychloride or by treating a diazonium salt (obtainable by nitrating, reducing and diazotising the resulting amine) with sulphur dioxide in the presence of a copper salt to give, for example, 4-chloro-benzophenone - 41 - sulphochloride, 4 - chloro - 21 - carboxy - benzphenone - 3 - sulphochloride, 4 - chloro - benzophenone - 3 : 41 - disulpho - chloride, sodium 4-methyl-benzophenone-3 : 41-disulphonate and 4-chloro-3-benzophenone-3-sulphonamide-31-sulpho-chloride.