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Updated: Sep 8, 2025
Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
Polyoxometalate-Incorporated Metal-Organic Network as a Heterogeneous Catalyst for Selective Oxidation of Aryl
Wen-Jing Cui1, Si-Meng Zhang1, Yuan-Yuan Ma1
1Hebei Key Laboratory of Organic Functional Molecules; National Demonstration Center for Experimental Chemistry Education; College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang, Hebei 050024, People's Republic of China.
Abstract:
Selective oxidation of aryl alkenes is important for chemical synthesis reactions, in which the key lies in the rational design of efficient catalysts. Herein, four polyoxometalate (POM)-incorporated metal-organic networks, with the formulas of [Co(ttb)(H2O)3]2[SiMo12O40]·2H2O (1), [Co(ttb)(H2O)2]2[SiW12O40]·8H2O (2), [Zn(Httb)(H2ttb)][BW12O40]·9H2O (3) and {[Zn(H2O)3(ttb)]4[Zn3(H2O)6]}[H3SiW10.5Zn1.5O40]2·24H2O (4) (ttb = 1,3,5-tri(1,2,4-triazol-1-ylmethyl)-2,4,6-trimethylbenzene), were hydrothermally synthesized and structurally characterized. Structural analysis showed that compound 1 consists of a POM-encapsulated three-dimensional (3-D) supramolecular framework; compound 2 is composed of a POM-supported 3-D coordination network; and compounds 3-4 show POM-incorporated 3-D supramolecular networks. Using selective catalytic oxidation of styrene as the model reaction, compounds 1-4 as heterogeneous catalysts display excellent performance with the double advantages of high styrene conversion and benzaldehyde selectivity owing to the synergistic effect among POM anions and transition metal (TM) centers. Among them, compound 1 exhibits the highest performance with ca. 96% styrene conversion and ca. 99% benzaldehyde selectivity in 3 h. In addition, compound 1 also displays excellent substrate compatibility, good reusability, and structural stability. Thus, a plausible reaction pathway for the selective oxidation of styrene is proposed. This study on the structure-function relationship paves a way for the rational design of POM-based heterogeneous catalysts for important catalysis applications.
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