Modular dehydrogenative cross-nucleophile coupling for direct construction of tetrasubstituted carbons

Abstract

The development of a unified platform for the cross-nucleophile coupling of tertiary C(sp³)–H bonds with diverse nucleophiles, ideally using readily available catalysts and inexpensive and green oxidants, remains a compelling challenge. We now asserted the FeCl₃-catalyzed cross-dehydrogenative coupling reaction between ortho-hydroxyl benzylic tertiary C(sp³)–H bonds and diverse nucleophiles under an air atmosphere for the rapid construction of various types of C–Y (Y = C, N, O, S) bonds. This reaction enables the modular dehydrogenative cross-nucleophile coupling for the direct construction of tetrasubstituted carbons featuring broad substrate tolerance and environmental friendliness. In addition, the highly functionalized benzofuroindoline core could also be facilely synthesized by the direct transformation from the in situ reduction/cyclization or nucleophilic addition/cyclization of 3,3-disubstituted lactams.