Patent GB-670038-A (GB)
Title: Improvements in photographic sensitizing dyes
IPC: C09B23/10
Filed: 1949-05-21
Abstract: A dye of the general formula <FORM:0670038/IV (c)/1> wherein R is an alkyl, alkoxyalkyl, or aryl group, R1 is an alkyl, substituted alkyl, or unsaturated alkyl group, D is a divalent o-arylene radical (e.g. an o-phenylene or o-naphthylene radical), d is 1, 2, or 3, J is CN, COOH, or a carbalkoxy, or acyl group, and Q is a benzfuryl or substituted benzfuryl radicle, or carbalkoxy group, or J and Q together represent the atoms necessary to complete a 5- or 6-membered heterocyclic nucleus or a 5-membered carbocyclic nucleus is prepared by bringing together at a reaction temperature and in the presence of a basic condensing agent either a quaternary salt of the general formula <FORM:0670038/IV (c)/2> wherein X is an anion, and a compound of the general formula <FORM:0670038/IV (c)/3> wherein R2 is H or an acyl group, R3 is an aryl group, and m is 1, 3, or 5, or a compound having the general formula <FORM:0670038/IV (c)/4> and a compound of the general formula <FORM:0670038/IV (c)/5> 5 - [(1 - 3 - Dimethyl - 2 - benzimidazolydidene)-ethylidene] - 3 - ethylrhodanine is prepared by refluxing together 1 : 2 : 3-trimethylbenzimidazolium iodide, 5 - acetanilidomethylene - 3-ethylrhodanine, and triethylamine.  5-[(1 : 3-Diethyl - 2 - benzimidazolylidene) - ethylidene]-3 - ethylrhodanine, 5 - [(1 : 3 - diethyl - 2 - benzimidazolylidene) - ethylidene] - 3 - ethyl - 2 - thio2 : 4 - oxazolidinedione, 5 - [(1 : 3 - diethyl - 2-benzimidazolylidene) - ethylidene] - 3 - ethyl-2 : 4 - imidazolidione, 5 - [(1 : 3 - diethyl - 2-benzimidazolylidene) - ethylidene] - 2 - diphenylamino - 4 - thiazolone, 5 - [(1 : 3 - diethyl - 2-benzimidazolylidene) - ethylidene] - 2 - imino - 4-thiazolidone, 3 - ethyl - 5 - [(1 : 3 - diethyl - 2-naphth - (1 : 2) - imidazolylidene) - ethylidene] rhodanine, 3 - ethyl - 5 - [(3 - b  - hydroxyethyl-1 - phenyl - 2 - benzimidazolylidene) - ethylidene]-rhodanine, 1 : 3 - diethyl - 5 - [(1 : 3 - diethyl - 2-benzimidazolylidene) - ethylidene] - 2 - thiobarbituric acid, 5 - [(1 : 3 - diethyl - 2 - benzimidazolylidene) - ethylidene] - 3 - phenylrhodanine, 1 : 3 - diethyl - 5 - [4 - (1 : 3 - diethyl - 2 - benzimidazolylidene) - 2 - butenylidene] - 2 - thiobarbituric acid, 1 - benzthiazyl - 4 - [4 - (1 : 3-diethyl - 2 - benzimidazolylidene) - 2 - butenylidene] - 3 - methyl - 5 - pyrazolone, 1 : 3 - diethyl - 5 - [6 - (1 : 3 - diethyl - 2 - benzimidazolylidene) - 2 : 4 - hexadienylidene) - 2 - thiobarbituric acid, 1 : 3 - diethyl - 5 - [4 - (1 : 3 - diethyl - 2-benzimidazolylidene) - 2 - butenylidene] - barbituric acid, 1 : 3 - diethyl - 5 - [4 - (1 : 3 - diethyl-2 - benzimidazolylidene) - 2 - butenylidene] - 2-thiohydantoin, 2 - [4 - (1 : 3 - diethyl - 2 - benzimidazolylidene) - 2 - butenylidene] - 1 : 3-indanedione, 2 - [4 - (1 : 3 - di - n - amyl - 2-benzimidazolylidene) - 2 - butenylidene] - 1 : 3-indanedione, 5 - [4 - (1 : 3 - diethyl - 2 - benzimidazolylidene) - 2 - butenylidene] - 3 - ethylrhodanine, 5 - [4 - (1 : 3 - diethyl - 2 - benzimidazolylidene) - 2 - butenylidene] - 3 - ethyl - 1-phenyl - 2 - thiohydantoin, 5 - [4 - (1 : 3 - diethyl-2 - benzimidazolylidene) - 2 - butenylidene] - 3-ethyl - 2 - thio - 2 : 4 - oxazolidinedione, 2 - [4-(1 : 3 - diethyl - 2 - benzimidazolylidene) - 2-butenylidene] - cyanacetylbenzfuran, diethyl-[4-(1 : 3 - diethyl - 2 - benzimidazolylidene) - 2-butenylidene] - malonate, and ethyl 2 - [4 - (1 : 3 - diethyl - 2 - benzimidazolylidene) - 2-butenylidene] - acetoacetate are similarly prepared. Specification 344,409 is referred to.  2 - (2 - Arilirovinyl) - 1 : 3 - diethylbeninidazolium iodide is prepared by heating together 1 : 3 - diethyl - 2 - methylbenzinidazolium iodide and diphenylformanidine.  2 - (2 - Acetanilidovinyl) - 1 : 3 - diethylbenzimidazolium iodide is prepared by refluxing together 2 - (2 - arilirovinyl) - 1 : 3 - diethyl benzimidazolium iodide and acetic anhydride.  4 - (3 - Acetanilidoallylidene) - 1 - (2 - benzthiazolyl) - 3 - methyl - 5 - pyrazolone is prepared by refluxing together 1-(2-benzthiazolyl)-3-methyl-5-pyrazolone, b -anilinoacrolein anilhydrochloride, and acetic anhydride.  2 - [3 - (Acetanilidoallylidene) - cyanecetyl)]-benzfuran, 3 - acetanilidoallylidene malonate, and ethyl 2-(3-acetanilidoallylidene)-acetoacetate are similarly prepared.  The Specification as open to inspection under Sect. 91, comprises also the production of dyes of the general formula in which J is a carbamyl group or a heterocyclic nucleus of the quinoline series and of dyes of the general formula in which Q is OH, NH2, or alkyl, aryl, or hydroxy group.  The preparation of 1-ethyl-5 - [6 - (1 : 3 - diethyl - 2 - benzimidazolylidene)-2 : 4-hexadienylidene] - oxindole is described.  This subject-matter does not appear in the Specification as accepted.