Synthesis 2022; 54(02): 490-498
DOI: 10.1055/a-1592-6394
paper

Tetrabutylammonium Iodide Mediated Sulfenylation of Poly­substituted 1H-Pyrazol-5-amines with Arylsulfonyl Hydrazides

Jing He
,
Yueting Wei
,
Xuezhen Li
,
Bin Dai
,
Ping Liu

We gratefully acknowledge the financial support of this work by the National Natural Science Foundation of China (No. 21563025).


Abstract

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.

Supporting Information



Publication History

Received: 28 July 2021

Accepted after revision: 19 August 2021

Accepted Manuscript online:
19 August 2021

Article published online:
12 October 2021

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