Metal-free photocatalytic aerobic hydroxylation of benzene catalyzed by the commercially available quinoline sulfate

Metalfree photocatalytic aerobic hydroxylation of benzene to phenol is achieved by using the low-cost commercially available quinoline sulfate (QuH(2)SO(4)) as the photocatalyst. The reaction conditions are optimized and a high phenol yield of 11.3% is obtained under the optimal reaction conditions. It is found that the [QuH](+) cation is the catalytic active species and its planar structure is crucial for its effect interaction with benzene. Moreover, the influence of the coupled anion on the photocatalytic activity of the [QuH](+) cation is investigated and discussed.