Oxygen-doped carbon nitride for enhanced photocatalytic activity in visible-light-induced decarboxylative annulation reactions

An oxygen atom-doped modification strategy was developed to improve the photocatalytic activity of graphite-like carbon nitride (g-C3N4), which was successfully employed as a reusable photocatalyst in the cascade annulation reaction of N-sulfonyl ketimines with N-aryl glycines. The oxygen-doped g-C3N4 (denoted as OCN) displays better catalytic performance than bulk g-C3N4 under visible light irradiation. Moreover, this heterogeneous photocatalyst can be easily recovered and recycled at least 5 times without loss of activity. Such a strategy would offer an expansion for the development of novel heterogeneous photocatalysts and their applications in organic synthesis.