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)2·2DMF·MeCN (1), [MoS4Cu4(dppm)4](NO3)2·MeCN (2) [MoS4Cu3(dppm)3](ClO4)·4H2O (3), [WS4Cu3(dppm)3](NO3)·4H2O (4), [WS4Cu3(dppm)3]SCN·CH2Cl2 (5), and [WS4Cu3(dppm)3]I·CH2Cl2 (6) [dppm = bis (diphenylphosphanyl)methane] were synthesized. Compounds 1–4 were obtained by the reactions of (NH4)2MS4 (M = Mo, W) with [Cu2(μ2-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)2WS4 with dppm and CuSCN (or CuI) in CH2Cl2/CH3OH. These clusters were characterized by single-crystal X-ray diffraction as well as IR, 1H NMR, and 31P 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.