Anodic desulfurization of dithioacetals of ketones in the presence of Et3N·3HF provided the corresponding gem-difluorocompounds while dithioacetals of aromatic and aliphatic aldehydes gave gem-difluoro thioethers and monofluoro thioether, respectively.
Photoreactions of various dithioacetals and ketals using tris(p-chlorophenyl)pyrylium perchlorate as a sensitizer were studied. Irradiation (λ&>360 nm) of dichloromethane solutions containing dithioacetals or ketals and pyryliumsalt afforded the corresponding carbonyl compounds in good to excellent yields in the presence of molecular oxygen.