Visible- light photocatalytic trifluoromethylation of arenes using graphene oxide as a metal- free photocatalyst

Photocatalytic trifluoromethylation has been considered as an efficient method to introduce trifluoromethyl groups into organic substances. However, the relatively high cost and toxic feature of the metalbased photocatalysts have become major obstacles for their further applications in this area. In this work, graphene oxide sheets have been successfully utilized as a kind of metal- free photocatalyst for the trifluoromethylation of arenes, using inexpensive CF3SO2Na as the CF3 radical source. It is shown that graphene oxide sheets exhibit suitable bandgaps under visible light irradiation to photocatalyse the oxide CF3SO2Na to form the electrophilic radical CF3, which efficiently induces the trifluoromethylation of typical benzene molecules and some of their derivatives.