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Heterobimetallic drive and cooperativity lead to a striking scenario for C–H bond activation and heteroaggregation involving MoIIIdimers. Reaction of (RO)3MoMo(OR)3with molar excess of ZnMe2at–78 °C affords the novel mixed Zn, Mo oxo clusters [Mo2(MeZn)6(μ2-Me)(μ3-CH2)2(OR)7] 1(R = neopentyl) and 2(R = cyclohexyl) preserving the MoMo triple bond, while the same reaction performed at ambient temperature gives rise to the related cluster [Mo2(MeZn)6(μ2-CH2)(μ3-CH2)2(OR)6] 3. These complexes represent the first examples of heterobimetallic MoMo complexes with bridging methyl and methylene groups and agostic C–H→Mo interactions, as well as penta-coordinate carbon. The complexes 1–3were characterized by elemental analyses, multinuclear NMR and single-crystal X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

A convenient and efficient synthesis of the stable monolithium alkylzinc alkoxo cubanes {Li(thf)(RZn)3(OR')4} [R = Me, R' = iPr (1), tBu (2); R = Et, R' = iPr (3), tBu (4)] is reported. They are well soluble in organic solvents and suitable molecular precursors for the formation of Li-containing ZnO nanoparticles. The compounds are accessible by a convenient one-pot reaction of the respective dialkylzinc with lithium alkoxides in the presence of water and can be isolated as white solids in 35-50% yield. Higher yields (80-85%) for 1 and 3 can be achieved by applying excess iPrOH instead of H2O as protolysis source. The compounds 1-4 were characterized by elemental analyses, multinuclear NMR and FT-IR spectroscopy, and single-crystal X-ray diffraction analysis (1 and 2). Interestingly, thermal treatment of solutions of 1 and 2, respectively, in anhydrous benzyl alkohol at 190 °C yields pure and highly crystalline Li-containing ZnO nanoparticles as evidenced by powder X-ray diffraction analysis (PXRD), Transition Electron Microscopy (TEM), FT-IR and 7Li MAS NMR spectroscopy. [ABSTRACT FROM AUTHOR]