Scandium-catalyzed tandem selective oxirane ring-opening/Friedel–Crafts alkylation: a facile access to [1,4]oxazino[4,3-a]indoles and 3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazines

Abstract

A facile technique involving a novel Lewis-acid-catalyzed tandem selective ring-opening of oxirane and Friedel–Crafts alkylation of 1H-indol-1-yl derived oxiranes was developed. The developed protocol affords functionalized [1,4]oxazino[4,3-a]indoles and 3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazines in up to 95% yield.