Synthesis, crystal structure of a novel metal–organic framework and its catalyzing properties on the selective oxidation of cyclohexene to cyclohexenone

Abstract

The development of a novel heterogeneous catalyst for effectively catalyzing target reactions with specific selectivity is an intriguing issue. Considering that the metal–organic frameworks (MOFs) exhibited excellent prospect in catalytic chemistry, a novel MOF [Ni3(OABDC)2(bipy)3 (H2O)6]n(CH3OH)n(H2O)4.5n (1) was synthesized in this study using the hydrothermal method with the coordination of 3, 5-dicarboxyphenoxyacetic acid (H3OABDC) and 4, 4′-bipy ligand with nickel(II) nitrate. The structure of MOF 1 was characterized by single-crystal diffractions. In the crystal of MOF 1, the H3OABDC connected the metal nodes to form 2D wavy layer structure while the 4, 4′-bipy connected the wavy layers to form a 3D porous framework through double helix coordination. Their diameters of the porous are about 15.914 Å×15.289 Å and 16.030 Å×15.289 Å, respectively. Interestingly, MOF 1 presented efficiency and selective catalytic performance for oxidizing cyclohexene into cyclohexenone using oxygen in the air under heterogeneous conditions. The average conversion rate of cyclohexene is 84.2%, and the catalytic selectivity for oxidation product cyclohexenone is 72.7%.