Mechanism of Visible Light-Mediated Alkene Aminoarylation with Arylsulfonylacetamides

Alkene aminoarylation with arylsulfonylacetamides via a visible light-mediated radical Smiles-Truce rearrangement represents a convenient approach to the privileged arylethylamine pharmacophore traditionally generated by circuitous, multistep sequences. Herein, we report detailed synthetic, spectroscopic, kinetic, and computational studies designed to interrogate the proposed mechanism, including the key aryl transfer event. The data are consistent with a rate-limiting 1,4-aryl migration occurring either via a stepwise process involving a radical Meisenheimer-like intermediate or in a concerted fashion dependent on both arene electronics and alkene sterics. Our efforts to probe the mechanism have significantly expanded the substrate scope of the transformation with respect to the migrating aryl group and provide further credence to the synthetic potential of radical aryl migrations.

Automated summary

Alkene aminoarylation with arylsulfonylacetamides via visible light-mediated radical Smiles-Truce rearrangement is a convenient method for synthesizing the traditional arylethylamine pharmacophore generated by multistep reactions. Our detailed study on the mechanism suggests that the reaction may proceed through a stepwise process or concerted fashion.