Photocatalytic alkoxylation of benzene with 3-cyano-1-methylquinolinium ion

One-pot alkoxylation of benzene with alcohols occurs under photoirradiation of 3-cyano-1-methylquinolinium ion in an oxygen-saturated acetonitrile solution containing benzene and alcohols. The photocatalytic reaction mechanism was clarified by nanosecond laser flash photolysis. The photocataytic alkoxylation of benzene is initiated by photoinduced electron transfer from benzene to the singlet excited state of 3-cyano-1-methylquinolinium ion, followed by the nucleophilic addition of alcohols to benzene radical cation. In the case of photoethoxylation, the optimal product and quantum yields of ethoxybenzene were 20% and 10%, respectively. (C) 2012 Optical Society of America