Alkoxyl Radical-Mediated Ring Expansion/1,4-Difunctionalization of 1,3-Enynes upon Copper Catalysis

Org Lett. 2023 Aug 4;25(30):5563-5568. doi: 10.1021/acs.orglett.3c01809. Epub 2023 Jul 21.

Abstract

A redox-neutral copper-catalyzed cascade reaction involving alkoxyl radical-mediated ring expansion/1,4-difunctionalization of 1,3-enynes was developed, offering a straightforward approach to the tetra-substituted allenes with macrolactone, CN, and CF3 functional groups. Remarkably, incorporation of the NH2 group onto the 1,3-enyne moiety enabled further cyclization to give a unique scaffold containing a lactone and an indole moiety.