Visible-Light-Mediated Energy Transfer Enables the Synthesis of β-Lactams via Intramolecular Hydrogen Atom Transfer

Abstract

The synthesis of 2-azetidinones (β-lactams) from simple acrylamide starting materials by visible-light-mediated energy transfer catalysis is reported. The reaction features a C(sp3)−H functionalization via a variation of the Norrish–Yang photocyclization involving a carbon-to-carbon 1,5-hydrogen atom transfer (supported by deuterium labelling and DFT calculations) and can be used for the construction of a diverse range of β-lactam products.