Regioselective electrochemical cascade C–H sulfonylation–bromination of indolizines to access difunctionalized indolizines

Abstract

Regioselective electrochemical C–H sulfonylation–bromination between indolizines, sodium sulfinates, and KBr has been established in an undivided cell, in which KBr serves as both the brominating agent and electrolyte. This consecutive C3–H sulfonylation and C1–H bromination protocol enables the synthesis of difunctionalized indolizine derivatives under catalyst- and oxidant-free conditions. Moreover, electrochemical C–H sulfonylation–thiocyanation/selenylation/thiolation of indolizines was realized via a two-step process. This protocol features excellent regioselectivity and environmentally friendly electrolysis.