One-Pot Two-Step Strategy for Efficient Synthesis of 3-Aryl-4-(arylthio)-1H-pyrazol-5-amines Derivatives

Abstract

One-pot two-step reaction of 3-oxo-3-arylpropanenitriles, methyl hydrazinecarboxylate (or hydrazine hydrate), and arylsulfonyl hydrazides has been established, and a series of 3-aryl-4-(arylthio)-1H-pyrazol-5-amines were constructed by sequential cyclization, sulfenylation, and removal of COOMe group under the action of I2 and N-iodo-succininide (NIS), respectively. The method represents good atomic economy, mild reaction conditions, broad substrate scope, and gram-scale synthesis. Moreover, the further transformations of 3-aryl-4-(arylthio)-1H-pyrazol-5-amine products were also investigated.