Synthesis and Structural Characterization of Six Pentanuclear and Tetranuclear Mo/W‐Cu‐S Clusters with Bis(diphenylphosphanyl) Methane

Six heterothiometalic clusters, namely, [WS4Cu4(dppm)(4)](ClO4)(2)center dot 2DMF center dot MeCN (1), [MoS4Cu4(dppm)(4)](NO3)(2)MeCN center dot (2) [MoS4Cu3(dppm)(3)](ClO4)center dot 4H(2)O (3), [WS4Cu3(dppm)(3)](NO3)center dot 4H(2)O (4), [WS4Cu3(dppm)(3)]SCN center dot CH2Cl2 (5), and [WS4Cu3(dppm)(3)]I center dot CH2Cl2 (6) [dppm = bis (diphenylphosphanyl)methane] were synthesized. Compounds 1-4 were obtained by the reactions of (NH4)(2)MS4 (M = Mo, W) with [Cu-2((2)-dppm)(2)(MeCN)(2)(ClO4)(2)] {or [Cu(dppm)(NO3)](2)} in the presence of 1,10-phen in mixed solvent (CH3CN/CH2Cl2/DMF for 1 and 2, CH2Cl2/CH3OH/DMF for 3 and 4. Compounds 5 and 6 were obtained by one-pot reactions of (NH4)(2)WS4 with dppm and CuSCN (or CuI) in CH2Cl2/CH3OH. These clusters were characterized by single-crystal X-ray diffraction as well as IR, H-1 NMR, and P-31 NMR spectroscopy. Structure analysis showed that compounds 1 and 2 are saddle-shaped pentanuclear cationic clusters, whereas compounds 3-6 are flywheel-shaped tetranuclear cationic clusters. In 1 and 2, the MS42- unit (M = W, Mo) is coordinated by four copper atoms, which are further bridged by four dppm molecules. In compounds 3-6, the MS42- unit is coordinated by three copper atoms and each copper atom is bridged by three dppm ligands.