Novel Heterotetranuclear V2Mo2 or V2W2 Complexes with 4,4′-Di-tert-butyl-2,2′-bipyridine: Syntheses, Crystal Structures, and Catalytic Activities

Two novel heterotetranuclear complexes [V2O2(μ-MeO)2(μ-WO4)2(4,4′-tBubpy)2] (1) and [V2O2(μ-MeO)2(μ-MoO4)2(4,4′-tBubpy)2] (2) were synthesized, and the solid state structures of these complexes were revealed by single crystal X-ray crystallography. The heterotetranuclear complexes 1 and 2 are centrosymmetric building blocks, considered as consisting of two [VO(4,4′-tBubpy)]3+ units bridged by μ-MO42– (M = W or Mo) anions connected with methoxy groups. Furthermore, catalytic activities of 1 and 2 in the alcohol oxidation with hydrogen peroxide as terminal oxidants in water as solvent were investigated.