C–H Oxidation/Michael Addition/Cyclization Cascade for Enantioselective Synthesis of Functionalized 2‑Amino‑4<i>H</i>‑chromenes

A streamlined method for the enantioselective synthesis of 2-amino-4<i>H</i>-chromenes from readily available 2-alkyl-substituted phenols and active methylene compounds bearing a cyano group with up to 97% ee is presented. This reaction is a cascade procedure including manganese dioxide mediated C–H oxidation for the generation of <i>o</i>-quinone methides and bifunctional squaramide-catalyzed Michael addition/cyclization