Geminal C-Cl and Si-Cl bond activation of chloromethanes and chlorosilanes by gallanediyl LGa.

The activation of relatively inert E-X σ-bonds by low-valent main group metal complexes is receiving increasing interest. We here confirm the promising potential of gallanediyl LGa (L = HC[C(Me)N(Dip)] 2 , Dip = 2,6-i-Pr 2 C 6 H 3 ) to activate E-Cl (E = C, Si) σ-bonds of group 14 element compounds. Equimolar reactions of LGa with chloromethanes and chlorosilanes EH x Cl 4- x (E = C, x = 0-2; E = Si, x = 0, 1) occurred with E-Cl bond insertion and formation of gallylmethanes and -silanes L(Cl)GaEH x Cl 3- x (E = C, x = 2 (1), 1 (2), 0 (3); E = Si, x = 1 (4)). In contrast, consecutive insertion into a geminal E-Cl bond was observed with two equivalents of LGa, yielding digallyl complexes [L(Cl)Ga] 2 EH x Cl 2- x (E = C, x = 2 (5); E = Si, x = 1 (6), 0 (7)). Compounds 1-7 were characterized by heteronuclear NMR ( 1 H, 13 C, 29 Si (4, 6)), IR spectroscopy and elemental analysis, and their solid-state structures were determined by single-crystal X-ray diffraction (sc-XRD).