Electrochemically-promoted synthesis of benzo[ b]thiophene-1,1-dioxides via strained quaternary spirocyclization

Chem Sci. 2022 Jul 28;13(34):9940-9946. doi: 10.1039/d2sc01175a. eCollection 2022 Aug 31.

Abstract

We report an approach for the synthesis of benzothiophene motifs under electrochemical conditions by the reaction of sulfonhydrazides with internal alkynes. Upon the formation of a quaternary spirocyclization intermediate by the selective ipso-addition instead of an ortho-attack, the S-migration process was rationalized to lead to the products. Computational studies revealed the selectivity and the compatibility of drug molecules showcased the potential application of the protocols.