Binding and Activation of Aromatic Molecules by a Molybdenum π-Base

Compounds having the form TpMo(NO)(1-methylimidazole)(η2-Lπ) (Tp = hydridotris(pyrazolyl)borate; Lπ = cyclohexene, naphthalene, furan, thiophene, and acetone) were synthesized in 31−41% yield by the reduction of TpMo(NO)Br2 in the presence of 1-methylimidazole and the respective π-acidic organic ligand. The structure of the naphthalene complex was confirmed by single-crystal X-ray diffraction. Degradation studies showed the bound aromatics to have half-lives of 37−236 h in acetone solution at 20 °C. A tandem addition across the bound ring of the naphthalene complex yielded a free 1,2-dihydronaphthalene in 80% yield following decomplexation.