Copper(II)‐Catalyzed Cascade Reactions of <i>N</i>‐Aryl Nitrones and Disubstituted Allenoates to Prepare [1,3]Oxazino[3,2‐a]indolines and Dihydropyrido[1,2‐a]indolines

Abstract We described a copper(II)‐catalyzed [3+2] cycloaddition of N ‐aryl‐α,β‐unsaturated nitrones with disubstituted allenoates bifurcated to prepare various [1,3]oxazino[3,2‐a]indolines and dihydropyrido[1,2‐a]indolines in moderate excellent yields. Mechanistic studies revealed that [1,3]oxazino[3,2‐a]indoline was kinetically favored product dihydropyrido[1,2‐a]indoline thermodynamically product. Moreover, the reaction easily performed at gram scales chiral could be obtained by using auxiliary. The present method highlights broad substrate scope, good functional group tolerance, diversity indoline scaffolds high diastereoselectivity. magnified image