Unusually selective synthesis of chlorohydrooligosilanes

New pathways towards molecular chlorohydrooligosilanes enable their one-pot synthesis in preparative amounts either by the selective chlorination of the corresponding perhydrosilanes with HCl/AlCl 3 or by the partial hydrogenation of perchlorooligosilanes with substoichiometric amounts of iBu 2 AlH. The unexpected selective formation of Cl 3 Si-substituted species in the partial hydrogenation reactions could be related to mechanistic aspects. Novel methods were developed for the synthesis of partially chlorinated higher silicon hydrides with unexpected selectivity.