Regio- and Diastereoselective Decarboxylative Allylation of N-Aryl α‑Amino Acids by Dual Photoredox/Nickel Catalysis

Homoallylic amines are important building blocks for the synthesis of nitrogen-containing natural products. They are generally synthesized by addition of allyl metal compounds to imines. With the establishment of photoredox catalysis in organic chemistry, research interest in homoallylic amine syntheses via radical reactions has increased. Herein, we present a dual photoredox/nickel catalyzed regio- and diastereoselective allylation reaction of N-aryl α-amino acids. Our method yields branched homoallylic amines in high yields and high syn-diastereoselectivity under mild and redox-neutral conditions. The synthetic flexibility of our reaction is demonstrated in a broad substrate scope, which is characterized by a high functional group tolerance. Detailed mechanistic studies revealed an imine as the key intermediate in this reaction.