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Indexed by:期刊论文

Date of Publication:2019-01-15

Journal:LANGMUIR

Included Journals:SCIE

Volume:35

Issue:2

Page Number:495-503

ISSN No.:0743-7463

Key Words:Bottles; Crystalline materials; Fourier transform infrared spectroscopy; Gas adsorption; Ionic liquids; Organometallics; Potassium compounds; Scanning electron microscopy, Carbonyldiimidazole; Condensation product; Diffusion kinetics; Heterogeneous catalyst; Metal organic framework; Nitrogen adsorption desorption; Physicochemical property; Powder X ray diffraction, Catalyst activity

Abstract:A novel heterogeneous catalyst, the ionic liquid (IL) of 1-butyl-3-methylimidazolium acetate (BmimOAc) immobilized on MIL-101-NH2, denoted as IL(OAc-)-MIL-101-NH2, was prepared by the "ship-in-a-bottle" strategy. The IL of BmimOAc was prepared in the MIL-101-NH2 nanocages primordially, in which the condensation product of MIL-101-NH2's amine group with 1,1'-carbonyldiimidazole (CDI) reacted with 1-bromo butane, and then the intermediate exchanged with potassium acetate. The structure and physicochemical properties of IL(OAc-)-MIL-101-NH2 were characterized by powder X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, DRS UV-vis, nitrogen adsorption-desorption, and elemental analysis. The results indicated that BmimOAc was anchored in the MIL-101-NH2 skeleton via the acylamino group and confined in the nanocages in the form of a single molecule. The composite material of IL(OAc-)-MIL-101-NH2 exhibited excellent catalytic activity and catalytically synthesized 3-aryl-2-oxazolone in an excellent yield of 92%. It can be reused up to six times without noteworthy loss of its activity and demonstrated distinct size-selective property for substrates. It was conjectured that the diffusion kinetics of reactants could be controlled by the aperture size of the metal-organic framework support.