Elucidating the promotional effect of a covalent triazine framework in aerobic oxidation

Synergistic catalysis holds great promise to enhance the catalytic performance of heterogeneous catalysts suffering from sluggish reaction kinetics. Much effort has been dedicated to the development of bimetallic systems in which the two promoter elements display synergistic benefits compared to monometallic counterparts. However, the use of bimetallic catalysts inescapably raises the cost of preparation and environmental issues. This study discovers a synergistic effect when using a bipyridine covalent triazine framework (bipy-CTF) as support for an IrIII complex in the aerobic oxidation reaction. The detailed mechanistic study provides insights into the function of the bipy-CTF in this synergistic catalysis. The EPR and in-situ XANES analyses confirm the applicability of bipy-CTF to activate oxygen and alcohol, resulting in an enhancement of the performance of the IrIII complex to exceed the activity of the homogeneous counterpart. This is an unprecedented report on promoting the activity of a heterogeneous catalyst through its solid support.