Enantioselective synthesis of tetrahydrocyclopenta[b]indole bearing a chiral quaternary carbon center via Pd(<scp>ii</scp>)–SPRIX-catalyzed C–H activation

Abstract

The highly enantioselective cyclization of 3-alkenylindole via C-H activation has been established using Pd(OCOCF₃)₂ in conjunction with the chiral spiro bis(isoxazoline) ligand (SPRIX). The presence of an N-allyl substituent on the substrate has a strong impact on both reactivity and selectivity, leading to tricyclic indole products (up to 96% ee) with a chiral quaternary carbon center.