Preparation and characterization of triangular clusters [M₃Q₄(acac)₃(py)₃]⁺ (M=Mo, W; Q=S, Se)

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• 作者：Hern&aacute ; ndez-Molina ; Rita ; Sokolov ; Maxim ; Clegg ; William ; Esparza ; Pedro ; Mederos ; Alfredo
• 关键词：Molybdenum ; Tungsten ; Chalcogenide clusters ; Acetylacetonate ; Pyridine ; Crystal structures
• 刊名：Inorganica Chimica Acta
• 出版年：2002
• 出版时间：March 28, 2002
• 年：2002
• 卷：331
• 期：1
• 页码：52-58
• 全文大小：400 K

文摘

Reactions of [M₃Q₄(H₂O)₉]⁴⁺ with acetylacetone (Hacac) and pyridine (py) in weakly alkaline solutions (pH 8–9) give mixed-ligand complexes [M₃Q₄(acac)₃(py)₃]⁺ (M=Mo, W; Q=S, Se), isolated as hexafluorophosphate salts. For M=Mo, Q=S and for M=W, Q=both S and Se, X-ray structural analysis has been carried out. The three compounds are isostructural and crystallize as [M₃Q₄(acac)₃(py)₃]PF₆·CHCl₃. Each M is attached to one capping (μ₃) and two bridging (μ₂) chalcogen atoms, one pyridine ligand and one chelating acetylacetonate ligand. The latter are coordinated symmetrically in positions trans to the μ₂-Q bridges to give cluster cations with crystallographic threefold rotation symmetry (point group 3m or C_3v). The structure is preserved in solution. CV experiments show two almost reversible waves due to consecutive one electron reductions with the ease of reduction decreasing in the order, Mo₃S₄>Mo₃Se₄>W₃Se₄>W₃S₄. FAB MS data are also discussed.