Supramolecular assemblies directed by hydrogen bonds and π-π Interactions and based on N-heterocyclic-ligand-modified β-octamolybdate - Structure and catalytic application in olefin epoxidation

摘要

A series of supramolecular assemblies based on POMs modified by organic ligands, including (Himi)_4[(imi)_2(Mo_8O _(26))] ·H_2O (1), (H_2bbi) _2[Mo_8O_(26)] (2), and (H_2bbi)[(Hbbi) _2 (Mo_8O_(26))] ·H_2O (3), were synthesized by a one-step hydrothermal method. All of them are active catalysts for the epoxidation of olefins with tert-butyl hydroperoxide as the oxidant. Most interestingly, (Himi)_4[(imi)_2(Mo_8O _(26))] ·H_2O (1) exhibits very high catalytic activity and stability, which makes it a truly efficient heterogeneous catalyst for olefin epoxidation.