Photoredox-Catalyzed Isomerization of Highly Substituted Allylic Alcohols by C-H Bond Activation

Angew Chem Int Ed Engl. 2020 Jul 6;59(28):11660-11668. doi: 10.1002/anie.202000743. Epub 2020 May 8.

Abstract

Photoredox-catalyzed isomerization of γ-carbonyl-substituted allylic alcohols to their corresponding carbonyl compounds was achieved for the first time by C-H bond activation. This catalytic redox-neutral process resulted in the synthesis of 1,4-dicarbonyl compounds. Notably, allylic alcohols bearing tetrasubstituted olefins can also be transformed into their corresponding carbonyl compounds. Density functional theory calculations show that the carbonyl group at the γ-position of allylic alcohols are beneficial to the formation of their corresponding allylic alcohol radicals with high vertical electron affinity, which contributes to the completion of the photoredox catalytic cycle.

Keywords: C−H bond activation; allylic alcohols; high substitution; isomerization; photoredox catalysis.