GB1166655A - Improved Photographic Colour Process and Light-Sensitive Elements - Google Patents

Abstract

1,166,655. Benzothiazoles. GEVAERTAGFA N.V. 24 Aug., 1967 [19 Sept., 1966], No. 41637/66. Heading C2C. [Also in Division G2] Compounds of the formula wherein D is hexadecyl, R 2 is hydrogen, R 1 is methyl or phenyl and Z is a benz ring which is unsubstituted or is substituted by chloro, fluoro, sulpho, trifluoro - methyl, difluoromethylsulphonyl, sulphamoyl or p - chlorophenylsulphamoyl, are made by heating an appropriately substituted 2 - methylmercapto - 3- methyl (or phenyl) - benzothiazolium quaternary salt with a carboxy-alkoxy-benzene sulphonyl hydrazide in pyridine. A compound of the above formula where D and R 2 are as above, R 1 is methyl and Z represents the 4: 6-dichlorobenz radical is made by heating 3-methyl-4: 6- dichloro - benzothiazolone - 2 - hydrazone with 2 - hexadecyloxy - 5 - carboxy - benzene sulphonyl chloride in the presence of zinc oxide and N-methyl-pyrrolidone; and a compound of the above formula where D is hexadecyl, R 2 is ethyl, R 1 is methyl and Z is the benz radical is made by esterifying the corresponding compound where R 2 is hydrogen with ethanol and hydrogen chloride. 2 - Methylmercapto - 3 - methyl - 6 - sulphobenzothiazolium p - toluenesulphonate, 2- methylmercapto - 3 - methyl - 5 - sulpho - benzothiazolium p - toluenesulphonate, 2 - methylmercapto - 3 - methyl - 5 - difluoromethylsulphonylbenzothiazolium p - toluenesulphonate and 2- methylmercapto - 3 - methyl - 5 - chloro - benzothiazolium methosulphate are made by quaternizing the corresponding 6- or 5-sulpho or 5- difluoromethylsulphonyl 2-methylmercaptobenzothiazole with methyl p-toluenesulphonate or by quaternizing 2-methylmercapto-5-chlorobenzothiazole with dimethyl sulphate. 2 - Methylmercapto - 3 - methyl - 5 - trifluoromethyl-benzothiazolium methosulphate is made by treating 2-mercapto-5-trifluoromethylbenzothiazole with dimethylsulphate at room temperature and then at 150‹ C. 2 - Methylmercapto - 3 - methyl - 5 - p - chlorophenylsulphamoylbenzothiuzolium methosulphate is made by heating 2-mercapto-5-p-chlorophenylsulphamoylbenzothiazole with dimethyl sulphate. 2 - Methylmercapto - 5 - sulpho - benzothiazole and 2 - methyl - mercapto - 5 - difluoromethylsulphonyl-benzothiazole are made by heating the corresponding 2-mercapto compounds with dimethyl sulphate. 2 - Methylmercapto - 6 - sulphobenzothiazole is made by sulphonating 2-methylmercaptobenzothiazole with 30% oleum. 2 - Mercapto - 5 - sulphobenzothiazole potassium salt and 2-mercapto-5-difluoromethylsulphonylbenzothiazole are made by reacting potassium 3-nitro-4-chloro-benzene sulphonate or 2- nitro - 4 - difluoromethylsulphonyl - chlorobenzene with sodium sulphide/H 2 S and then with CS 2 and acidifying with acetic acid. 2 - Mercapto - 5 - fluoromethylbenzothiazole is made by heating with CS 2 in sodium ethylate a yellow precipitate obtained by treating with Zn dust, HCl and acetic acid, bis (2-nitro-4-trifuoromethylphenyl) disulphide obtained by reacting 2- chloro-5-trifluoromethyl-nitrobenzene with sodium sulphide and sulphur. 3 - Methyl - 4: 6 - dichlorobenzothiazolone - 2- hydrazone is made by heating with hydrazine hydrate, a quaternary salt obtained by quaternizing with methyl p-toluene sulphonate 2- amino - 4; 6 - dichlorobenzothiazole prepared by treating 2: 4-dichlorophenylthiourea with Br 2 in CHC1 3 and then ammonia solution. 3 - Carboxy - 4 - hexadeoyloxy - benzene sulphonyl hydrazide is made by reacting the corresponding sulphonyl chloride with hydrazine hydrate in dioxan. 6 - Sulphamido -, 6 - fluoro - and 6 - chloro- 3 - methyl - benzothiazolin - 2 - ones are prepared by subjecting the corresponding 2-iminobenzothiazoles to nitration and reaction with phosphorus pentasulphide.