Regioselective N1- and N2-heterocycloalkylation of N1-sulfonyl-1,2,3-triazoles

Abstract

Considering the high synthetic value of N¹- and N²-substituted compounds, we developed a tuneable and visible-light-driven three-component reaction between N¹-sulfonyl-1,2,3-triazoles, saturated heterocycles, and N-bromosuccinimide to form N¹- or N²-heterocycloalkylated 1,2,3-triazoles that are not easily accessible by conventional strategies. The visible-light-driven reaction generally proceeds smoothly and with excellent regioselectivity. In particular, the α-N²-1,2,3-triazole-β-halogenation of saturated heterocycles (formal C–C single bond difunctionalization) provided the corresponding products with excellent stereoselectivity.