Visible-light-promoted and chlorophyll-catalyzed aerobic desulfurization of thioamides to amides.

A novel method for the metal-free synthesis of amides from thioamides based on visible-light photoredox catalysis and in an air atmosphere is reported. Natural pigment chlorophyll is used as a photosensitizer to generate singlet molecular oxygen O, which is involved in the aerobic desulfurization of thioamides. The protocol provides amides in good yields at room temperature under mild conditions. On the basis of experimental results, a plausible photoredox mechanism is proposed.