Inventors:
Chang K. Kim - Pittsford NY
Wayne N. Lamicela - Rush NY
David L. Allen - Holcomb NY
Assignee:
Eastman Kodak Company - Rochester NY
International Classification:
C07D48704
Abstract:
Pyrazolotriazoles such as 3,6-disubstituted-1H-pyrazolo[5,1-c]-1,2,4-triazoles: ##STR1## are useful in the photographic arts, e. g. as magenta couplers. They may be made from 3,6-disubstituted-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazines: ##STR2## by a two-step process. The first step comprises a ring contraction and a diacylation. The second step comprises hydrolysis of the acyl groups and desulfurization. The second step is conducted using an aqueous mixture of a hydrohalic acid such as hydrochloric acid and hypophosphorous acid, H. sub. 3 PO. sub. 2. When the hypophosphorous acid is used, less sulfur and sulfur-containing impurities are formed.