Synergistic Effect of FeII and MnII Ions in Cyano-Bridged Heterometallic Coordination Polymers on Catalytic Selectivity of Benzene Oxygenation to Phenol

A cyano-bridged heterometallic coordination polymer with partial deficiencies of CN-ligands, [Mn-II(H2O)(8/3)](3/2)[Fe-II(CN)(5)(NH3)], forms open metal sites both on MnII and FeII ions by liberation of monodentate ligands such as NH3 and H2O. [Mn-II(H2O)(8/3)](3/2)[Fe-II(CN)(5)(NH3)] exhibits high catalytic activity and selectivity of benzene oxygenation to phenol in the presence of m-chloroperoxybenzoic acid as an oxidant. The postcatalytic spectroscopy of [Mn-II(H2O)(8/3)](3/2)[Fe-II(CN)(5)(NH3)] and catalysis comparison with a physical mixture of [Mn-II(H2O)(3)](2)[Fe-II(CN)(6)] and [Fe(H2O)(3/2)](4/3)- [Fe(CN)(6)], which has open metal sites on both Mn-II and Fe ions separately, indicated that the high activity resulted from high oxidation ability and phenol adsorption ability of Fe-II and Mn-II ions, respectively.

Automated summary

A cyano-bridged heterometallic coordination polymer, [Mn-II(H2O)(8/3)](3/2)[Fe-II(CN)(5)(NH3)], forms open metal sites on both MnII and FeII ions. It exhibits high catalytic activity and selectivity for benzene oxygenation to phenol. Comparative studies show that the high activity is attributed to the high oxidation ability of FeII and the phenol adsorption ability of MnII.