Unexpected Hydrolithiation of M=M Double Bond (M, M = Si, Ge) with tBuLi

The reduction of 2- and 1-disilagermirenes 1 and 2 with tBuLi proceeded regio- and stereospecifically to produce germyllithium derivative 4—the product of the formal addition of LiH across the M=Mʹ bond (M, Mʹ= Si, Ge) through single electron transfer steps. Reduction of 1,2-disila-3-germacyclopenta-2,4-diene derivative 3 with tBuLi also proceeded specifically, but with an opposite regioselectivity to form silyllithium derivative 7.