Patent GB-428359-A (GB)
Title: Improvements in or relating to the production of dyestuffs
IPC: C09B23/16
Filed: 1933-10-03
Abstract: Compounds suitable for the treatment of photographic emulsions are prepared by condensing rhodanic acid or other compound containing as part of a five-membered ring the system <FORM:0428359/IV/1> or a tautomeric form thereof (in which X represents H, alkyl, aryl, or aralkyl) with a quaternary salt of an organic nitrogen compound containing an anilidovinyl or acetanilidovinyl group which may be represented by the formula <FORM:0428359/IV/2> wherein n is 1 or 2, Y stands for hydrogen, alkyl or acetyl, Z stands for H or a part of a ring including W, W stands for a phenyl residue or part of a ring including Z, R stands for hydrogen or an alkyl group and T for an acidic radicle.  A modification of this process comprises condensing the rhodanic acid or other compound with a g -anilido or g -acetanilido derivative of a quaternary salt of a heterocyclic nitrogen compound derived by reacting a g -methyl derivative with a diphenylformamidine.  A modification of these processes comprises condensing the rhodanic acid or other compound with an arylamidine and then condensing the resulting product with a quaternary salt of a heterocyclic nitrogen base containing a reactive methyl group. Compounds specified in place of rhodanic acid are oxindole, hydantoin, thiohydantoin and pseudohydantoins; compounds containing reactive anilidovinyl or acetanilidovinyl groupings are the salts of substituted or unsubstituted thiazoles, thiazolines, oxazoles, oxazolines, selenazoles, selenazolines, quinolines, indolenines, pyridines, benzthiazole, naphthathiazole, benzoxazole, naphthoxazole, pyrimidines, quinazolines; of these the polyclic compounds may be substituted by hydroxy, alkoxy, halogen, alkyl, aryl, aralkyl, amino or substituted amino in the carbocylic ring.  In examples: (1) rhodanic acid is condensed with 1 - o  - acetanilidovinylbenzthiazole ethyl iodide, and with 1 - 3 . 3 - trimethyl - 2 - o  - acetanilidovinylindoleninium iodide, in both cases in presence of pyridine; with glutaconic aldehydedianilide chloride and with the corresponding N . N<1> - dimethyl derivative, in both cases in presence of alcoholic sodium alcoholate; with diphenylformamidine in acetic anhydride followed by condensation of the resulting intermediate with 2-methylbenzthiazole ethiodide and with quinaldine ethochloride; (2) 2 . 4 - dihydroxythiazole is condensed with 1 . 3 . - trimethyl - 2 - o  - acetanilidoindoleninium iodide in presence of pyridine; (3) thiohydantoin is condensed with 2-o -acetanilidovinylbenzoxazole ethiodide in presence of pyridine and with N . N<1> - dimethylglutaconic aldehyde dianilide chloride in presence of alcoholic sodium alcoholate.  In all cases reaction occurs between the methylene group in b -position to the nitrogen atom of the five-membered ring and the anilido &c. group to give a compound having a completely conjugated chain of carbon atoms between this nitrogen atom and that of the second reactant of the above formula.  The Provisional Specification refers to the condensation of a substance containing the group --CH2CO--NX-- (X being as above) with a substance containing a nitrogen atom (either in a ring or as an external group to a ring or as part of a chain) and a reactive group. Reference is made in addition to the use of 1-phenyl-3-methyl-5-pyrazolone, barbituric acid, ketodihydrobenzparathiazine, benzo-b - morpholone, homophthalimide, succinimide, malonamide, dihydrocarbostyrils, oxydihydroquinoxaline, and to the condensation with these of p-nitrosodimethylaniline; also of formimino ethers, b -anilinoacrolein anil, glutaconic aldehyde dianilide followed by reaction of the products so obtained with heterocyclic nitrogen bodies having reactive a - or g -methyl groups.