PREPARATION OF BIS(TETRABUTYLAMMONIUM) OCTA(MU-3-CHLORO)HEXAKIS(TRIFLUOROMETHANESULFONATO)-OCTAHEDRO-HEXAMOLYBDATE(2-), (BU4N)2[MO6CLI8(CF3SO3)A6] - A VERSATILE STARTING MATERIAL FOR SUBSTITUTED MO(II) CLUSTERS CONTAINING THE [MO6CLI8]4+ CORE

The useful starting material (Bu4N)2[Mo6Cl(i)8(CF3SO3)a6], was synthesized in high yield by the reaction of (Bu4N)2[Mo6Cl(i)8Cl(a)6] with AgCF3SO3 in CH2Cl2. The crystal structure of thc benzyltrimethylammonium salt of this cluster reveals an average Mo-Mo distance of 2.593 (4) angstrom, an average Mo-Cl distance of 2.465 (4) angstrom, and an average Mo-O distance of 2.126 (9) angstrom. The triflate ligands, CF3SO3-, are readily substituted by other ligands. Convenient routes are reported for the preparation of the clusters [Mo6Cl(i)8X(a)6]2-, X = Cl-, Br-, I-, SCN-, OMe-, CH3CO2-, CH3C6H4SO3-, and CF3CO2-; the latter three are new. These anionic clusters were characterized by IR, UV-vis and fast atom bombardment mass spectrometry. Solution IR data of the title compound in dimethylformamide are consistent with the complete displacement of the triflate ligands by thc solvent, only partial displacement is observed in acetone, and the cluster retains all CF3SO3- ligands in CH2Cl2. The isolation of the new cationic clusters, [Mo6Cl(i)8L(a)6],4+ with L = C5H5NO, (C6H5CH2)2SO, and (C6H5)3PO, as triflate salts is also described. Crystal data for (BzMe3N)2[Mo6Cl(i)8(CF3SO3)a6] are as follows: triclinic space group, P1BAR (No. 2); a = 11.036 (2) angstrom, b = 11.553 (3) angstrom, c = 12.010 (2) angstrom; alpha = 79.05 (2)-degrees, beta = 78.06 (1)-degrees, gamma = 86.58 (2)-degrees; V = 1471 (1) angstrom3; Z = 1.