Synthesis and Crystal Structure of an Octa-nuclear V-Cu-S Cluster:[VS_3O(CuPBu_3)_2(CuSPBu_3)]_2

The title compound has been synthesized by reaction of (NH4)3VS4,CuCl, and PBu3 in CH2Cl2 and its structure was determined by single crystal X-raydiffraction. Crystallographic data: C72 H162 Cu6O2P6S8V2, Mr= 1985. 57, monoclinicspace group C2/c, a= 17. 864(3), b= 25. 946(8), c= 24.071 (7),β= 112. 79(2)°,V = 10285. 9, Z= 4, Dc= 1. 28 g/cm3, F(000) = 4192, μ(MoKa) = 16. 7 cm-1,the final R=0.065 and Rw =0.074 for 4051 unique reflections with I 3σ(I). Thestructure can be described as a metal-sulfur dodecahedral cage fused by two incompletecubane-like VS3Cu3 units connected by Cu - S bonds. The Cu - S bonds within theasymmetric VS3Cu3 unit are slightly shorter than those linking the two centrosymmetrically related VS3Cu3 units. The six copper and two vanadium atoms display asomewhat distorted cubane array with a μ4-S atom on each face of the metal cubane.