A Zinc(II) Porous Metal-Organic Framework and Its Morphologically Controlled Catalytic Properties in the Knoevenagel Condensation Reaction

Chempluschem. 2017 Sep;82(9):1182-1187. doi: 10.1002/cplu.201700327. Epub 2017 Sep 6.

Abstract

A new metal-organic framework (MOF), {Zn(oba)(3-bpdh)0.5 } ⋅2 H2 O (1 Zn; oba=4,4'-oxybis(benzoic acid), 3-bpdh=N,N'-bis(1-pyridine-3-yl-ethylidene)hydrazine), was successfully assembled in a solvothermal system. The Zn2+ ion center located in a five-coordinate environment combined with oba to produce a layer-like structure, which is again linked with 3-bpdh to yield a 3D channel framework. MOF 1 Zn microcrystals with different morphologies were synthesized through coordination modulation and solvent-dependent methods. The effects of the concentration of the modulator, the reaction temperature, and the volume ratio of mixed solvents have been investigated. Furthermore, the catalytic performance in Knoevenagel condensation was studied for different morphologies of 1 Zn microcrystals; this revealed that the MOF microcrystals exhibited excellent and morphology-dependent catalytic properties.

Keywords: heterogeneous catalysis; metal-organic frameworks; solvent effects; structure-activity relationships; zinc.