Photocatalytic Asymmetric Acyl Radical Truce–Smiles Rearrangement for the Synthesis of Enantioenriched α‐Aryl Amides

Abstract

AbstractThe radical Truce–Smiles rearrangement is a straightforward strategy for incorporating aryl groups into organic molecules for which asymmetric processes remains rare. By employing a readily available and non‐expensive chiral auxiliary, we developed a highly efficient asymmetric photocatalytic acyl and alkyl radical Truce–Smiles rearrangement of α‐substituted acrylamides using tetrabutylammonium decatungstate (TBADT) as a hydrogen atom–transfer photocatalyst, along with aldehydes or C−H containing precursors. The rearranged products exhibited excellent diastereoselectivities (7 : 1 to >98 : 2 d.r.) and chiral auxiliary was easily removed. Mechanistic studies allowed understanding the transformation in which density functional theory (DFT) calculations provided insights into the stereochemistry‐determining step.