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

Abstract

The reaction of GeCl₂·dioxane with 1,4-diazabutadiene compounds [(HCNAr)₂, Ar = 2,6-iPr₂C₆H₃, (1); Ar = 2,4,6-Me₃C₆H₂, (2)] leads to the formation of dichlorogermane derivatives [{N(2,6-iPr₂C₆H₃)CH}₂]GeCl₂ (3) and [{N(2,4,6-Me₃C₆H₂)CH}₂]GeCl₂ (4) respectively. The reaction of compound 2 with SiCl₂·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·NMe₃ in toluene leads to the dihydrogermane [{N(2,6-iPr₂C₆H₃)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-iPr₂C₆H₃)CH}₂]Ge (8).