Patent GB-623990-A (GB)
Title: Improvements in and relating to the manufacture of carbocyanine dyes and the sensitising of photographic silver halide emulsions by means thereof
IPC: C07D277/84
Filed: 1945-11-01
Abstract: 2-Methylene - 3 - methyl - a  - naphthathiazoline is prepared by treating an ethanol solution of 2 : 3-dimethyl-a -naphthathiazole with aqueous sodium hydroxide. 2-Methylene-3 : 6-dimethylbenzthiazoline, 2-methylene-3-methyl-6-methoxyquinoline, 2 - methylene - 3 - ethylbenzthiazoline, 2 - methylene - 3 - benzylbenzthiazoline, 2-methylene - 3 - methyl - b  - naphthathiazoline, 2-methylene - 3 - methyl - 6 - chlorobenzthiazoline, 2-methylene - 3 - methyl - 6 - methoxybenzthiazoline, 2 - methylene - 3 : 6 - dimethylbenzselenazoline, 2 - methylene - 3 - methyl - 6 - acetylaminobenzthiazoline, and 2 - methylene - 3 - ethylbenzselenazoline are similarly prepared.  3 - Methyl - dihydro -4 : 5 - benzbenzthiazolylidene-(2)-dithioacetic acid is prepared by adding carbon disulphide to an ethanol solution of 2-methylene-3-methyl-a -naphthathiazoline.  3 : 6 - Dimethyl - dihydrobenzthiazolylidene-(2)-dithioacetic acid, 3 - methyl - dihydrobenzselenazolylidene - (2) - dithioacetic acid, 3 - benzyl - dihydrobenzthiazolylidene-(2)-dithioacetic acid, 3-methyl-dihydro - 6 : 7 - benzbenzthiazolylidene - (2) - dithioacetic acid, 3 - methyl - 6 - chlorodihydrobenzthiazolylidene - (2) - dithioacetic acid, 3 - ethyl-6-dimethylaminodihydrobenzthiazolylidene - (2) - dithioacetic acid, 3 - methyl - 6 - dimethylamino - dihydrobenzthiazolylidene - (2) - dithioacetic acid, 3 - ethyldihydrobenzthiazolylidene - (2) - dithioacetic acid, 3-methyl-6-methoxydihydrobenzthiazolylidene - (2) - dithioacetic acid, 3-ethyldihydrobenzselenazolylidene - (2) - dithioacetic acid, 3 - methyl-5 : 6 - dimethoxydihydrobenzthiazolylidene - (2) - dithioacetic acid, 3-methyl-a -(dihydrobenzthiazolylidene) - (2) - dithiopropionic acid, 3 - methyl - a  - (dihydrobenzselenazolylidene) - (2) - dithiopropionic acid, 3 : 6 - dimethyldihydrobenzselenazolylidene-(2)-dithioacetic acid, 3-methyl-6-methylmercapto-dihydrobenzthiazolylidene - (2) p  - dithioacetic acid, 1 - ethyl-6-methoxy - dihydroquinolylidene - (2) - dithioacetic acid and 1-methyl-5 : 6-benzdihydroquinolylidene-(2)-dithioacetic acid.  2 - b  - Bis - (methylmercapto) - vinyl - benzthiazolemethyl-methosulphate is prepared by heating 3 - methyldihydrobenzthiazolylidene - (2) - dithioacetic acid with dimethyl sulphate.  2-b -Bis-(methylmercapto) - vinyl - benzselenazole - methyl - methosulphate 2 - b  - bis - (ethylmercapto) - vinyldihydrobenzselenazolylidene methobromide (by reacting the product with potassium bromide), 2-b -bis-(ethylmercapto)-vinyl-dihydrobenzthiazolylidene methiodide (by reacting the product with potassium iodide), 2-b -bis-(ethylmercapto)-vinyl-4 : 5-benzbenzthiazole methobromide (by reacting the product with potassium bromide), 2-b -bis-(ethylmercapto) - 6 - methyl - benzthiazole methio - dide (by reacting the product with potassium iodide), and 2 - b  - bis - (ethylmercapto) - a  - methyl - vinyl-benzthiazole methiodide (by reacting the product with potassium iodide) are similarly prepared. Specification 472,227 is referred to.ALSO:Meso-alkylmercapto-substituted and meso-substituted-alkylmercapto-substituted symmetrical and unsymmetrical carbocyanine dyes are prepared by reacting quaternary ammonium salts of nitrogen-containing heterocyclic bases containing a reactive methyl group with substances of the formula <FORM:0623990/IV (c)/1> wherein Y is vinylene, arylene, or -CH2-CH2, which may be substituted, Z is S, Se, -C(CH3)2, or -CH=CH-, R and R1 are alkyl or substituted alkyl, and X is an acid residue.  The reaction may be effected in presence of solvents and/or condensing agents.  In example (1) 2 - b  - bis - (methylmercapto) - vinylbenzthiazole methyl methosulphate is heated with 2 : 3 - dimethylbenzthiazole methosulphate, and potassium bromide solution is added to give the dye 3 : 31-dimethyl-9-methylmercaptothiacarbocyanine bromide.  The dyes 3 : 31-dimethyl - 9 - methylmercaptothiathiazolinocarbocyanine iodide, 3 : 31 - dimethyl - 9 - methylmercapto - 41 : 51 - benzthiacarbocyanine iodide, 3 : 31 - dimethyl - 9 - methylmercaptothiaselenacarbocyanine iodide, 3 : 31 : 61 - trimethyl - 9-methylmercaptothiacarbocyanine iodide, 3 : 31-dimethyl - 9 - methylmercaptothiaselenacarbocyanine bromide, 3 : 31 : 61 - trimethyl - 9-ethylmercaptoselenacarbocyanine iodide, 3 : 31-dimethyl - 9 - ethylmercaptothiaselenacarbocyanine bromide, 3 - methyl - 31 - ethyl - 9-ethylmercaptothiaselenacarbocyanine iodide, 3 - 31 : 61 - trimethyl - 9 - ethylmercapto - thiaselenacarbocyanine iodide, 3 : 31-dimethyl - 61-methoxy - 9 - ethylmercapto - thiaselenacarbocyanine iodide, 3 : 31 - dimethyl - 9 - ethylmercapto - 41 : 51 - benzthiacarbocyanine iodide, 3 : 31 - dimethyl - 9 - ethylmercaptothiathiazo linocarbocyanine iodide, 3 : 11 - dimethyl - 9 ethylmercapto - 4 : 5 - benzthia - 21 - cyanine iodide, 3 : 31 - dimethyl - 61 - dimethylamino-9 - ethylmercapto - 4 : 5 - benzthiacarbocyanine iodide, 3 : 31 - dimethyl - 9 - ethylmercapto-4 : 51-benzthiaselenacarbocyanine bromide, 3 : 31-dimethyl - 9 - ethylmercapto - 4 : 5 : 61 : 71-benzbenzthiacarbocyanine bromide, 3 : 31 : 6 : 61-tetramethyl - 9 - ethylmercaptothiacarbocyanine iodie, and 3 : 31 - 8 - trimethyl - 9 - ethylmercaptothiaselenacarbocyanine bromide are similarly prepared.  Specification 472,227 is referred to.