A One-Pot Transformation of Furans to Nitrogen-Bearing Aromatic Polycycles Initiated by Singlet Oxygen

Vassilikogiannakis et al. have reported a one-pot transformation of simple furans to complex nitrogen-bearing aromatic polycycles initiated by singlet oxygen generated by light in the presence of rose Bengal as a photosensitizer. With the presumed reaction mechanism, they have shown that the intermediate 1,4-dielectrophiles which arise from the photo-oxygenation of furans using singlet oxygen are reacted with amines bearing an aromatic nucleus to form the intermediate 2-pyrrolidinones. This reaction goes under mild conditions and has wide functional group tolerance.