Blue, diamagnetic [{HB(Me2pz)3}W(CO)2]2(mu-S) (1) and [{HB(Pripz)3}W(CO)2]2(mu-S)(2)are formed upon reaction of {HB(Me2pz)3)WBr(CO)2, {HB(Me2pz)3}WH(CO)3, or {HB(Pripz)3}WH(CO)3 with propylene sulfide in refluxing 1,2-dichloroethane. Both complexes have been characterized by analytical, mass spectrometric, IR and H-1 NMR spectroscopic, and X-ray crystallographic studies. Crystal data for 1 : monoclinic space group C2/c, a = 20.315(5) angstrom, b = 14.450(3) angstrom, c = 13.796(2) angstrom, beta = 103.02(2)degrees, and V = 3945(1) angstrom3 with Z = 4. Crystal data for 2 : monoclinic space group P2(1), a = 11.433(5) angstrom, b = 14.354(7) angstrom, c = 15.058(4) angstrom, beta = 103.98(3)degrees, and V = 2397(1) angstrom3 with Z = 2. The structures were each refined by a full-matrix least-squares procedure to R = 0.027 for 3290 reflections with I greater-than-or-equal-to 3.0sigma(I) for 1 and R = 0.024 (4245 reflections) for 2. The dinuclear complexes are composed of distorted octahedral tungsten centers coordinated by fac-tris(pyrazolyl)borate, carbonyl, and bridging thio ligands. The triatomic [W2S]2+ Cores are characterized by short W-S distances (2.1809(3) angstrom for 1, 2.173(3) and 2.184(3) angstrom for 2) and nearly linear W-S-W bond angles (171.6(1)degrees for 1 and 175.3(1)degrees for 2).