Rearrangement of 5-Cyanouracils into 6-Aminouracils by Reaction with Amines and Hydroxide Ion

抄録

Treatment of 5-cyano-1-phenyluracil derivatives (1) with ammonia and alkylamines afforded 6-amino-5-iminomethyluracils (2) via rearrangement involving ring-opening and ring-closure processes. Upon reaction of 3-unsubstituted 5-cyano-1-phenyluracil (1d) with ammonia and methylamine, ring-opening products, 3-acryloyl-1-phenylureas (5a and 5b) were isolated and recyclized with ease to 6-aminouracils (2j and 2k). Employment of sodium hydroxide instead of amines caused analogous rearrangement to give 6-amino-5-formyluracils (7a-c).