Four novel Z-shaped hexanuclear vanadium oxide clusters as efficient heterogeneous catalysts for cycloaddition of CO2 and oxidative desulfurization reactions

Abstract

Chemical fixation of CO2 into C1 source, as a general approach, can effectively alleviate the emission of greenhouse gasses. Whereas, the challenge posed by the need for efficient catalysts with high catalytic active sites still exists. In this work, we reported a series of new hexavanadate clusters, [(C6H6ON)2(C2H8N2)2(CH3O)6VIV6O8] (V6–1), [(C6H6ON)2(C3H10N2)2(CH3O)6VIV6O8] (V6–2), [(C6H6ON)2(C6H14N2)2(CH3O)6VIV6O8] (V6–3) and [(C6H6ON)2(C4H11N2O)2(CH3O)4VIV6O8] (V6–4), assembled by 2-aminophenol and four different kinds of Lewis bases (LB), ethanediamine (en), 1,2-diaminopropane, 1,2-cyclohexanediamine and N-(2-hydroxyethyl)ethylenediamine (ben) together. Among them, the basic unit {V6} cluster featured Z-shaped configuration represents a brand-new example of hexanuclear vanadium clusters. Remarkably, the catalytic tests demonstrated that V6–1 as catalyst displays high catalytic activity in the cycloaddition for the CO2 fixation into cyclic carbonates by virtue of open V sites. As expected, for oxidative desulfurization of sulfides, V6–1 also exhibits satisfied catalytic effectiveness. Furthermore, the recycling test confirmed that catalyst V6–1 may be a bifunctional heterogeneous catalyst with great promise for both CO2 cycloaddition and oxidative desulfurization reactions.