Synthesis, Characterization, and Substitution Chemistry of [Bu₄N]₂[W₆Cl₈(OSO₂CF₃)₆]. A Versatile Precursor for Axially Substituted Clusters Containing the {W₆Cl₈}⁴⁺ Core

The new cluster [Bu₄N]₂[W₆Cl₈(OSO₂CF₃)₆] (1) has been prepared and structurally characterized. This material is an effective precursor for the generation of cluster ions with the general formula [W₆Cl₈L₆]ⁿ (L = Cl^-, Br^-, I^-, NCS^-, NCO^-, NCSe^-, and OPPh₃; n = 2− or 4+). The last three clusters are new. The products have been characterized by IR spectroscopy, NMR spectroscopy, and FAB mass spectrometry. In addition to 1, the products [Bu₄N]₂[W₆Cl₈(NCS)₆] (5) and [Bu₄N]₂[W₆Cl₈(NCO)₆] (7) were structurally characterized. Crystal data for 1:  space group, P2₁/c (No. 14); a = 11.116(5) Å; b = 27.952(1) Å; c = 24.516(1) Å; β = 95.182(9)°; V = 7586.3(5) ų; Z = 4. Crystal data for 5:  space group, P2₁/n (No. 14); a = 11.3323(9) Å; b = 12.3404(9) Å; c = 44.583(3) Å; β = 97.089(1)°; V = 6187.1(7) ų; Z = 4. Crystal data for 7:  space group, P1̄ (No. 2); a = 11.8009(8) Å; b = 11.9332(8) Å; c = 11.9522(8) Å; α = 77.904(1)°; β = 95.182(9)°; γ = 62.574(1)°; V = 1450.5(2) ų; Z = 1.