Enantioselective Catalytic Addition of N‐Acyl Radicals: In Batch and In Flow Organophotoredox α−Amination of Aldehydes

The organophotoredox catalytic enantioselective addition of N-acyl radicals to aldehydes, to afford enantioenriched N-acyl 1,2 aminoalcohols was studied.Under the best conditions,in batch,the product was isolatedin up to 52% yield and 85% e.e., usinga low cost and commercially available chiral imidazolidinone as organocatalyst. The reaction was then studied in flow, exploringdifferent experimental setups and photoreactors. Although modest yields were obtained, the in-flow process afforded the product in higher productivities (up to 60 times higher) and improved space time yields (increased upto 113 times)compared to the batch reaction,with no loss of stereoselectivity.