Reactivity of organogermanium and organotin trihydrides.

The organogermanium and organotin trihydrides (TbbEH) [E = Ge (3), Sn (7)] with the Tbb substituent were synthesized by hydride substitution (Tbb = 2,6-[CH(SiMe)]-4-(-Bu)CH). Deprotonation of the organoelement trihydrides 3 and 7 was studied in reaction with bases MeLi, BnK and LDA (Bn = benzyl, LDA = lithium diisopropylamide) to yield the deprotonation products (8-11) as lithium or potassium salts. Hydride abstraction from TbbSnH using the trityl salt [PhC][Al(OC{CF})] gives the salt [TbbSnH][Al(OC{CF})] (12) which was stabilized by thf donor ligands [TbbSnH(thf)][Al(OC{CF})] (13). Tintrihydride 7 reacts with trialkylamine EtMeN to give as the product of a reductive elimination of hydrogen the distannane (TbbSnH) (14). Transfer of hydrogen was observed in reaction of trihydrides TbbEH (E = Ge, Sn) and ArGeH with N-heterocyclic carbene (NHC). The NHC adduct TbbSnH(NHC) (15) was synthesized at rt and the germanium hydrides exhibit hydrogen transfer at higher temperatures to give ArGeH(NHC) (16) and TbbGeH(NHC) (17).