Facile synthesis of dichlorosilane by metathesis reaction and dehydrogenation of dihydrogermane by a frustrated Lewis pair

The reaction of GeCl(2 center dot)dioxane with 1,4-diazabutadiene compounds [(HC=NAr)(2), Ar = 2,6-iPr(2)C(6)H(3), (1); Ar = 2,4,6-Me3C6H2, (2)] leads to the formation of dichlorogermane derivatives [{N(2,6-iPr(2)C(6)H(3))CH}(2)]GeCl2 (3) and [{N(2,4,6-Me3C6H2)CH}(2)]GeCl2 (4) respectively. The reaction of compound 2 with SiCl2 center dot NHC (NHC = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidine) (5) results in the formation of dichlorosilane [{N(2,4,6-Me3C6H2) CH} 2] SiCl2 (6) which is the precursor for the synthesis of N-heterocyclic silylene. Furthermore the reaction of dichlorogermane 3 with two equivalents of AlH3 center dot NMe3 in toluene leads to the dihydrogermane [{N(2,6-iPr(2)C(6)H(3))CH}(2)]GeH2 (7). Interestingly this dihydrogermane (7) is dehydrogenated by the frustrated Lewis pair, N-heterocyclic carbene (1,3-di-tert-butylimidazol-2-ylidene) and tris(pentafluorophenyl) borane, to form the N-heterocyclic germylene [{N(2,6-iPr(2)C(6)H(3))CH}(2)] Ge (8).