PRODUCTION OF 5-AMINOPYRAZOLE BASED COMPOUND

摘要

PURPOSE:To obtain the titled compound useful as a raw material for photographic couplers, particularly magenta couplers readily in high yield, by reacting an imino alpha-acylacetate as a starting material with a hydrazine derivative. CONSTITUTION:An imino alpha-acylacetate expressed by formula I (R1 is alkyl, cycloalkyl, aryl or heterocyclic ring group; R2 is primary alkyl; A is m- basicprotonic acid; m is an integer 1-4; n is 0 or 1/m) as a starting material and a hyddrazine derivative expressed by formula II (R2 is H, alkyl, aryl or heterocyclic ring group) are dispersed in a dispersing medium, e.g. methyl alcohol or benzene, and reacted to give a compound expressed by formula III. The imino alpha-acylacetate which is the starting material is synthesized by synthesizing an acylacetonitrile from acetonitrile, and reacting the resultant acylacetonitrile with hydrogen chloride gas in an alcohol.