Synthesis of 3‑Spirocyclobutyl Oxindoles via N-Heterocyclic Carbene-Catalyzed Radical Alkylarylation of Bicyclo[1.1.0]butanes

Abstract

3-Spirocyclobutyl oxindoles and their derivatives represent a class of highly significant bioactive heterocycles in organic chemistry. Herein, an N-Heterocyclic Carbene(NHC)-catalyzed radical alkylarylation of Bicyclo[1.1.0]butanes (BCBs) for the convenient construction of 3-spirocyclobutyl oxindoles has been developed. This facile protocol features mild reaction conditions and high efficiency, transition metal free, and broad substrate scope (24 examples, up to 90% yield).