NaHSO3-Mediated Direct Synthesis of Sulfinic Esters from Sulfonyl Hydrazides under Transition-Metal-Free Conditions

We have developed a protocol for the NaHSO3-promoted esterification of sulfonyl hydrazides with alcohols for the synthesis of sulfinic esters. Various sulfonyl hydrazides could be converted to the corresponding sulfinic esters in good to high yields. The merits of this protocol include mild transition-metal-free reaction conditions, an inexpensive and available reagent, and operational simplicity. Controlled experiments reveal that this transformation probably undergoes via a radical pathway.

Automated summary

A new protocol for the synthesis of sulfinic esters via esterification of sulfonyl hydrazides with alcohols using NaHSO3 as the promoter has been developed. This method offers mild transition-metal-free reaction conditions, an inexpensive and readily available reagent, and operational simplicity. Controlled experiments suggest that the transformation likely proceeds through a radical pathway.