Expanding the Chemical Space of Electrophilic ß-Glycosyl ß-Lactams through Photoinduced Diastereoselective Functionalization.

Herein, we present a photoinduced diastereoselective C-3 functionalization of electrophilic ß-glycosyl ß-lactams. The developed protocol is simple, mild, and scalable and explores the use of 3-exomethylene ß-lactams as reaction partners in a Giese type reaction. The key nucleophilic alkyl radical is generated by a photoinduced electron transfer process in the EDA complex formed by NHPI and Hantzsch esters. The diastereoselective hydrogen atom transfer to the ß-lactam radical intermediate enables the synthesis of various N-phenyl ß-glycosyl ß-lactams.

Visible-Light Mediated Carbamoylation of Nitrones under a Continuous Flow Regime.

Herein, we report a rapid and scalable continuous-flow photocatalytic approach for the carbamoylation of nitrones. This protocol makes use of readily available 4-amido-1,4 dihydropyridines as carbamoyl radical precursors. The scope of this transformation exhibits high compatibility with complex structures containing amino acids, peptides, and glycosides. Importantly, the developed method allows a photocatalytic synthetic strategy in combination with flow conditions, maximizing the potential and efficiency for the synthesis of valuable α-(N-hydroxy)amino amides.