Atroposelective Synthesis of <i>N</i>-Arylindoles via Enantioselective N–H Bond Insertion

Abstract

We present here a rhodium-catalyzed asymmetric N–H insertion reaction, which is a concerted process revealed by DFT calculations, for the synthesis of novel axially chiral N-arylindoles by the reaction between indoles and diazonaphthoquinones. The reaction occurs at the N1 rather than C2/C3 positions of indoles, providing the chiral N-arylindoles in good yields and excellent enantiomeric ratios. Furthermore, this protocol is also amenable to the synthesis of chiral N-arylcarbazoles with excellent enantiocontrol.