Patent GB-620802-A (GB)
Title: Improvements in or relating to dyestuffs
IPC: C09B23/02
Filed: 1947-01-24
Abstract: Dye intermediates of the formula <FORM:0620802/IV (b)/1> wherein R1 is an alkyl or aralkyl group, D1 is the residue of a 5- or 6-membered heterocyclic ring, and n is 0 or 1, or the corresponding cyanomethyl derivative of the alkyl or aralkyl quaternary salt, with an alkyl or aralkyl quaternary salt of a 5- or 6-membered heterocyclic N compound having in the a - or g -position to the quaternary N atom an alkyl, aralkyl, or aryl thioethervinyl, thioetherbutadienyl, selenoethervinyl, or selenoetherbutadienyl group or a group of formula -(CH=CH)mNH2 (where m is 1, 2, or 3), or an N-acyl, N-aryl, or N-acylaryl derivative thereof, are prepared by reacting the corresponding alkyl or aralkyl quaternary salt of the heterocyclic N compound having a reactive halogen atom or thioether or selenoether group attached in the a - or g -position to the quaternary N atom with cyanacetic acid. 2-Cyanomethylene-3-methyldihydrobenzthiazole is prepared by fusing together 2 - methylmercaptobenzthiazole and methyl p-toluenesulphonate, adding cyanacetic acid and pyridine, and boiling.  2-Cyanomethylene - 3 - ethyldihydrobenzthiazole, 6 - nitro-2 - cyanomethylene - 3 - methyldihydrobenzthiazole, and 2 - cyanomethylene - 1 - ethyldihydroquinoline are similarly prepared. Samples have been furnished under Sect. 2 (5) of the Acts, of the dyes 2-(3-ethylbenzthiazole) - 21 - (1 : 3 : 3 - trimethylindolenine) - a  - cyanotrimethinecyanine iodide and p  2-(3-ethylbenzthiazole) - 41 - (1 - ethylquinoline) - a  - cyanoheptamethinecyanine iodide. Specification 552,921 is referred to.ALSO:Cyanine dyes are prepared by condensing together an intermediate of the general formula <FORM:0620802/IV (c)/1> wherein R1 is an alkyl or aralkyl group, D1 is the residue of a 5- or 6-membered heterocyclic ring, and n is 0 or 1, or the corresponding cyanomethyl derivative of the alkyl or aralkyl quaternary salt with an alkyl or aralkyl quaternary salt of a 5- or 6-membered heterocyclic N compound having in the a - or g -position to the quaternary N atom an alkyl, aralkyl, or aryl thioethervinyl, thioetherbutadienyl, selenoethervinyl or selenoetherbutadienyl group or a group of formula -(CH=CH)mNH2 (where m is 1, 2 or 3) or an N-acyl, N-aryl or N-acylaryl derivative thereof.  2 - (3 - Methylbenzthiazole) - 21 - (3 - methyl - 5 - chlorobenzthiazole)-cyanotrimethinecyanine iodide is prepared by refluxing together 2-ethylmercaptovinyl)-5-chlorobenzthiazole metho-p-toluenesulphonate, 2-cyanmethylene-3-methyl-dihydrobenzthiazole and pyridine, and pouring into aqueous KI solution. Bis-2-(3-ethylbenzthiazole)-a -cyanotrimethinecyanine iodide, 2-(1-methylquinoline) - 21 - (1 : 3 : 3 - trimethylin - dolenine) - a  - cyanotrimethinecyanine iodide and 2 - (1 - methylquinoline) - 21 - (3 - methylbenz - oxazole) - a  - cyanotrimethinecyanine iodide are similarly prepared.  Samples have been furnished under Sect. 2(5) of 2 - (3 - ethylbenzthiazole) - 21 - (1 : 3 : 3 - tri - methylindolenine) - cyanotrimethinecyanine iodide and of 2-(3-ethylbenzthiazole)-41-(1-ethylquinoline) - cyanoheptamethinecyanine iodide.  Specification 552,921 is referred to.