A Chiral Amine Transfer Approach to the Photocatalytic Asymmetric Synthesis of α-Trialkyl-α-tertiary Amines

A long-standing challenge within radical chemistry is that of controlling the absolute stereochemistry of the products. Here, we report the stereocontrolled addition of alpha-amino radicals reductively generated from imines via visible-light-mediated photo-redox-catalysis to alkenes, giving rise to enantioenriched alpha-trialkyl-alpha- tertiary amines. This process exploits a commercially available phenylglycinol derivative as a source of both nitrogen and chiral information. DFT studies support a stereochemical model whereby an intramolecular H-bond rigidifies the transition state of the enantiodetermining step.

Automated summary

We report the stereocontrolled addition of alpha-amino radicals to alkenes through visible-light-mediated photo-redox-catalysis, generating enantioenriched alpha-trialkyl-alpha- tertiary amines. This process utilizes a commercially available phenylglycinol derivative as a source of nitrogen and chiral information. DFT studies confirm the role of an intramolecular H-bond in rigidifying the transition state of the enantiodetermining step.