Pyrazolo(1,5-a)benzimidazole couplers
AssigneeEastman Kodak Company
InventorMichael W. Crawley
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Abstract
The invention provides a method for the production of a pyrazolo(1,5-a)benzimidazole of the general formula (A): ##STR1## wherein R is a substituted or unsubstituted alkyl or aryl group, and R.sup.1 -R.sup.4 =R, H, halogen, OR, COOR, CONHR, SO.sub.2, NO.sub.2 NHR, NR.sub.2, or CN, and X is hydogen or a reactive group releasable on coupling with an oxidized color developer, wherein the invention provides reacting a 2-amino or 2-mercapto substituted benzimidazole to form a triazepinone or a thiadiazino derivative respectively, ring contracting said triazepinone or thiadiazino derivative to give the corresponding 2-methylpyrazolobenzimidazole product, and subsequently removing the substituents at the -3 or -4 positions to provide a compound of the general formula (1).
Claims5
A method for the production of a pyrazolo (1,5-a) benzimidazole of the formula (A):
- ##STR9## wherein R is an alkyl or aryl group;
- R.sup.1 -R.sup.4 individually are R, H, halogen, or, COOR, CONHR, SO.sub.2, NO.sub.2, NHR, NR.sub.2, or CN;
- and,
- X is hydrogen or a group releasable on coupling with an oxidized color photographic developer, wherein the method comprises reacting a 2-amino or 2-mercapto substituted benzimidazole to form a triazepinone or a thiadiazino derivative respectively, ring contracting said triazepinone or thiadiazino derivative to give the corresponding 2-methylpyrazolobenzimidazole product, and subsequently removing the substituents at the -3 or -4 positions to provide a compound of the formula (A).
Dependencies are inferred from the claim text.