β-Functionalization of Saturated Aza-Heterocycles Enabled by Organic Photoredox Catalysis

ACS Catal. 2021 Mar 5;11(5):3153-3158. doi: 10.1021/acscatal.1c00099. Epub 2021 Feb 24.

Abstract

The direct β-functionalization of saturated aza-heterocycles has remained a synthetic challenge because of the remote and unactivated nature of β-C-H bonds in these motifs. Herein, we demonstrate the β-functionalization of saturated aza-heterocycles enabled by a two-step organic photoredox catalysis approach. Initially, a photoredox-catalyzed copper-mediated dehydrogenation of saturated aza-heterocycles produces ene-carbamates. This is followed by an anti-Markovnikov hydrofunctionalization of the ene-carbamates with a range of heteroatom-containing nucleophiles furnishing an array of C-C, C-O, and C-N aza-heterocycles at the β-position.

Keywords: anti-Markovnikov; catalysis; dehydrogenation; heterocycle; organic; photoredox.