Synthesis, structures and oxygen atom transfer catalysis of oxo-bridged molybdenum(V) complexes with heterocyclic bidentate ligands (N,X) X = S, Se

Abstract

The dinuclear mu-oxomolybdenum(V) complexes [Mo2O3(PyS)(4)] (1), [Mo2O3(PySe)(4)] (2) and [Mo2O3(4-CF3-PymS)(4)] (3) were obtained by similar reactions of the [MoO2Cl2(DME)] precursor with the corresponding heterocyclic bidentate (N,X) ligands, X = S, Se, where PyS, PySe and 4-CF3-PymS are the anions of pyridine-2-thione, pyridine-2-selenolato and 4-trifluoromethyl-2-pyrimidinthiol, respectively. All compounds were characterized by elemental analysis, IR, NMR, EI-MS spectroscopy and X-ray diffraction. The crystal structures of 1-3 all include the common [Mo2O3](4+) core. Compounds 1 and 2 are isostructural. The catalytic oxo-transfer properties of the molybdenum(V) compounds 1 and 2 were studied by the use of PPh3 in DMSO with a considerably higher catalytic activity for the thionato containing complex I than for its selenolato containing analogue 2. (C) 2007 Elsevier Ltd. All rights reserved.