Lacunary {Se4V10} Heteropolyoxovanadate Precursor with Monometal, Metal-Richer-Sandwiched Derivatives {Se8V20M} and {Se8V20M3}: Correlations between the Synthesis, Structure, and Catalytic Property

Abstract

A new family of trinuclear transition-metal (TM)-sandwiched heteropolyoxovanadates (hetero-POVs) [(SeV₁₀O₂₈(SeO₃)₃M(H₂O)₃)₂(M(H₂O)₄)]^10– (Se₈V₂₀M₃, where M = Mn²⁺, Co²⁺, and Zn²⁺) were prepared using two feasible approaches: a stepwise assembly strategy atop the POV precursor Se₄V₁₀ and a one-pot reaction approach of KVO₃, SeO₂, TM²⁺, and a proline ligand. The crystallographic studies reveal that Se₈V₂₀M₃ consist of two asymmetric [SeV₁₀O₂₈(SeO₃)₃M(H₂O)₃)]^6– units, linked by another TM²⁺ ion, thus forming an interesting staggered sandwich-type arrangement. Additionally, Se₈V₂₀M₃ and Se₈V₂₀M present strong correlations between their structures and catalytic properties. In particular, Se₈V₂₀M₃ demonstrate an analogical heterogeneous catalytic performance as Se₈V₂₀M in the sulfoxidation reaction of thioethers owing to their structural similarities.