A novel, zeolite-encapsulated μ3-oxo Co/Mn cluster catalyst for oxidation of para-xylene to terephthalic acid

Trinuclear, mu (3)-oxo mixed metal acetato complexes, [CoMn2(mu (3)-O)(MeCO2)(6)(py)(3)] (py = pyridine) encapsulated in zeolite HY, exhibit high catalytic efficiency in the selective aerial oxidation of para-xylene to terephthalic acid; interestingly, the formation of 4-carboxybenzaldehyde, the worrisome impurity in the conventional process, is suppressed significantly over these solid catalysts.