Synthesis and Structural Characterization of an Unusual Oxygen-Linked Double Cubane-Like Cluster {[Mo3PbOS3](OAc)2(py)3(dtp)2O}2

The unusual oxygen-linked double cubane-like cluster compound {[Mo3PbOS3](OAc)2(py)3(dtp)2O}2 (A) (dtp = S2P(OEt2)-, OAc = CH3COO-, py = C5H5N) was obtained for the first time by the reaction of the mixed S/O-bridged cluster [Mo3(μ3-O)(μ-S)3(dtp)4H2O] (B) with Pb(OAc)2·3H2O in the presence of excess CH3COOH and pyridine. It has been characterized by 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 with Mo−(μ-O) bond lengths of ca. 1.89 A. The cell dimensions are a = 11.705(8) A, b = 19.527(8) A, c = 20.670(9) A, β = 98.14(4)°, V = 4677(8) A3, Z = 2 in the space group P21/n. The final R = 0.056, Rw = 0.068 for 5424 reflections with I ≥ 3σ(I). The average Mo−Mo bond distance is 2.613(1) A and the nonbonding Mo−Pb distances lie in the range from 3.997(1) to 4.090(1) A. The spectra of IR, Raman, and UV−vis spectra are also shown in this paper.