Triply Selective & Sequential Diversification at C sp 3 : Expansion of Alkyl Germane Reactivity for C-C & C-Heteroatom Bond Formation.

We report the triply selective and sequential diversification of a single C sp 3 carbon carrying Cl, Bpin and GeEt 3 for the modular and programmable construction of sp 3 -rich molecules. Various functionalizations of C sp 3 -Cl and C sp 3 -BPin (e.g. alkylation, arylation, homologation, amination, hydroxylation) were tolerated by the C sp 3 -GeEt 3 group. Moreover, the methodological repertoire of alkyl germane functionalization was significantly expanded beyond the hitherto known Giese addition and arylation to alkynylation, alkenylation, cyanation, halogenation, azidation, C-S bond formation as well as the first demonstration of stereo-selective functionalization of a C sp 3 -[Ge] bond.