Synthesis and structural characterization of an unusual oxygen-linked double cubane-like cluster {[Mo3PbOS3](OAc)(2)(py)(3)(dtp)(2)O}(2)

The unusual oxygen-linked double cubane-like cluster compound {[Mo3PbOS3](O Ac)(2)(py)(3)(dtP)(2)O}(2) (A) (dtp = S2P(OEt2)(-), OAc = CH3COO-, py = C5H 5N) was obtained for the first time by the reaction of the mixed S/O-bridge d cluster [Mo-3(mu(3)-O)(mu-S)(3)(dtp)(4)H2O] (B) With Pb(OAc)(2) . 3H(2)O in the presence of excess CH3COOH and pyridine. It has been characterized b y IR, Raman, UV-vis, and X-ray structure analysis. The molecule contains a crystallographic center of inversion and can be viewed as consisting of two [Mo3PbOS3](6+) cubane-like cores linked through a pair of oxygen bridges w ith Mo-(mu-O) bond lengths of ca. 1.89 Angstrom. The cell dimensions are a = 11.705(8) Angstrom, b = 19.527(8) Angstrom, c = 20.670(9) Angstrom, beta = 98.14(4)degrees, V= 4677(8) Angstrom(3), Z = 2 in the space group P2(i/n) . The final R = 0.056, R-w = 0.068 for 5424 reflections with I greater than or equal to 3 sigma(I). The average Mo-Mo bond distance is 2.613(1) Angstr om and the nonbonding Mo-Pb distances lie in the range from 3.997(1) to 4.0 90(1) Angstrom. The spectra of IR, Raman, and UV-vis spectra are also shown in this paper.