A TBAI-mediated sulfenylation of N,3-diaryl-1-arylsulfonyl-1H-pyrazol-5-amines with arylsulfonyl hydrazides has been established, and an expanded inventory of N,5-diaryl-4-(arylthio)-1H-pyrazol-3-amines was constructed through C–S bond formation and N–S bond breaking. Mechanistic investigations suggest thiosulfonate as a key intermediate in the sulfenylation, and the detosylation is promoted by the generated arylsulfinic acid. The method is characterized by simple operating conditions, broad substrate range as well as gram-scale reaction.
通过TBAI介导的N,3-二芳基-1-芳磺酰基-1H-吡唑-5-胺与芳基磺酰肼的磺酰化反应已经建立,并通过C-S键形成和N-S键断裂构建了N,5-二芳基-4-(芳硫)-1H-吡唑-3-胺的扩展库存。机理研究表明硫代磺酸酯是磺酰化中的关键中间体,去磺酰作用由生成的芳基亚磺酸促进。该方法具有简单的操作条件、广泛的底物范围以及克级反应的特点。