Synthesis of Potassium Oligosilanides in Benzene

Abstract

Despite the initial assumption that the reaction of methylated oligosilanes, like (Me3Si)4Si, with tBuOK to afford potassium oligosilanides requires ethereal solvents or crown ether, we found that the reaction also proceeds in benzene. However, forced reaction conditions and long reaction times are required to obtain complete conversion. The related reaction of the phenyl-substituted oligosilane (PhMe2Si)3SiMe proceeds much faster and suggests interaction of the substrate's phenyl groups with the potassium ions, facilitating the reaction. Attempts to accelerate the reaction of methylated oligosilanes by using large excess amounts of tBuOK are successful. However, the silanides formed in this reaction co-crystallize with tBuOK.