Synthesis and X-ray crystal structures of two trinuclear molybdenum clusters coordianted by p-nitrobenzoate: Mo_3S_4(dtp)_3(p-NO_2C_6H_4COO)(L)

摘要

Two new trinuclear molybdenum clusters Mo_3S_4(dtp)_3(p-NO_2C_6H_4COO)(L) (dtp = diethyldithiophosphate, L = Py and DMF) have been synthesized by the ligand substitution reaction with p-nitrobenzoic acid using the precursors Mo_3S_4(dtp)_4(H_2O) and Mo_3S_4(dtp)_3(CCl_3COO)(Py), respectively. Their structures have been determined by X-ray diffraction analysis and confirmed by ~(31)P NMR spectra. Both compounds contain [Mo_3S_4] cores in which three Mo atoms form an isosceles triangle and each Mo atom is octahedrally coordinated. High asymmetry of coordination on the different Mo atoms is observed. The ligand replacement of -dtp by the aromatic acid makes the whole molecule more stable in a dipolar solvent. The coordiantion difference between Py and DMF also affects the core sructure, resulting in the corresponding Mo-Mo distances being different in these two similar cluster compounds.