Lanthanide metal–organic frameworks for catalytic oxidation of olefins

Abstract

Two isostructural lanthanide metal–organic frameworks (Ln-MOF-589, Ln = La³⁺, Ce³⁺), constructed from a tetratopic linker, benzoimidephenanthroline tetracarboxylic acid (H₄BIPA-TC), have been solvothermally synthesized and characterized. These Ln-MOF-589 materials consist of Lewis acid [Ln₂(-COO)₆(-COOH)₂(H₂O)₆] units and a naphthalene diimide core, which exhibited promising catalytic activity for the oxidation of olefins. Among them, Ce-MOF-589 exhibited outstanding performance with high conversions of styrene and cyclohexene (94 and 90%, respectively), and good selectivities towards styrene oxide and 2-cyclohexen-1-one (85, and 95%, respectively). Notably, the catalytic activity of Ce-MOF-589 outperformed that of homogeneous and heterogeneous catalysts, and representative MOFs. Also, Ce-MOF-589 can be recycled for at least up to six cycles with no significant loss of catalytic performance.