Hydrogenolysis and hydrogenation of β-O-4 ketones by a simple photocatalytic hydrogen transfer reaction

Efficient cleavage of CO bonds in lignin and its models is of great importance for the production of value-added aromatic compounds. A simple TiO2 photochemical approach was applied for β-O-4 ketone hydrogenolysis by an electron transfer photocatalytic reaction. The conversion of the substrate 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl) ethanone was 89.8% in 30 min, with the yield of products 4-methoxy acetophenone of 75.2% and o-methoxyphenol of 98.9%. Compared to the selective hydrogenolysis role of TiO2, Pd/TiO2 catalyst prefers to simultaneously catalyzing the hydrogenative cleavage of CO ether bond and the hydrogenation of CO to CHOH.