A novel mixed valence tetranuclear nitrosyl complex bridged by tetraoxomolybdate

The reaction of the molybdenum–dinitrosyl complexes with PPh3, using 2-pyrimidinethiolate (pymt) or 2-pyridinethiolate (pyt) as a thiolate ligand, was found to produce a dinuclear complex [{(ON)MoL2}2(μ-OH)2] (1) (L = pymt or pyt) and Ph3PO. In addition, the first reported example of a mixed valence molybdenum–nitrosyl tetranuclear complex, [Ph3POH]2[{(ON)Mo(pymt)2}2(μ-MoO4)2] (2), was produced by the reaction of 1(pymt) with Ph3PO. This is the first published nitrosyl complex containing both tetraoxomolybdate and thiolato ligands. The molybdenum and bridging oxygen atoms formed a novel eight-membered ring with a central porous structure.