Metal-free synthesis of sulfonylated indolo[2,1-<i>a</i>]isoquinolines from sulfur dioxide

Abstract

Access to sulfonylated indolo[2,1- a ]isoquinolines through an efficient three-component reaction of 2-aryl- N -acryloyl indoles, sulfur dioxide and aryldiazonium tetrafluoroborates is developed.