Eastman-kodak Company

David L Allen

Chang K Kim

Wayne N Lamicela

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.

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Holcomb, NY, United States of America

David L Allen