X-ray structures of tris(0-cyclohexyl-dithiocarbonato)bismuth(III) and tris(0-benzyl-dithiocarbonato)bismuth(III)

The crystal structures of two Bi tris xanthates are reported, namely [Bi(S₂CO-c-C₆H₁₁)₃ J and [Bi(S₂COCH₂C₆H₅)₃]. They exist as centrosymmetric dimers, owing to the presence of bridging xanthate ligands, with seven-coordinate Bi atoms. The presence of a stereochemically active lonepair of electrons in each structure distorts the coordination geometry defined by seven S atoms and causes the elongation of some of the Bi-S bond distances. Crystals of both compounds are triclinic, space groupP¯1 with unit cell dimensions for [Bi(S₂CO-c-C₆H₁₁)₃]:a=12.417(3),b=13.571(3),c=9.681(4) Å;=102.30(2),=109.21(2), =66.23(2)° andZ=2; and for [Bi(S₂COCH₂C₆H₅)₃]:a=14.747(2),b=15.966(2),c=5.991(1) Å;=95.08(1),=98.51(1), =104.92(1)° andZ=2. The structures were refined by a full-matrix least-squares procedure to finalR=0.045 using 4274 reflections for [Bi(S₂CO-c-C₆H₁₁)₃] and toR=0.027 using 3993 reflections for [Bi(S₂COCH₂C₆H₅)₃].