Abstract: | The synthesis and crystal structure of novel trinuclear molybdenum cluster compound with somewhat “loose” coordination site {Mo3(μ3-S)(μ-S)3S2P(OEt)2l4 ? P(C6H5)3} ? (0.86 CH2C12) have been reported. The cluster crystallizes in the space group with two molecules in a unit cell whose parameters are a=10.472(4), b=14.375(2), c=21.695(3)Å; α=74.04(1)°, β=76.50(2)°, γ=72.22 (2)°, V=2950Å3 and Do=1.693 g ? cm?3. On the basis of 4840 independent reflections with I≥2σ(I), the structure was solved by heavy atom method and Fourier method and refined by full-matrix least-squares techniques to a final R=0.058. The distances between Mo atoms in this cluster are 2.731(1), 2.748(1) and 2.753(1)Å respectively. The meat value of Mo—Mo bond lengths is slightly shorter than those in other trinuclear Mo clusters with “loosely coordinated” site. In addition, the PPh3 ligand is loosely coordinated to one Mo atom in direction opposite to the μ3-S with Mo—P bond length of 2.647(3)Å. This is different from the other structurally analogous clusters, in which the loosely coordinated ligand is trans to μ2-S. A summary of Mo—Mo and Mo—L bonding for such clusters is given. |