Hypervalent Hydrosilicates Connected to Light Alkali Metal Amides: Synthesis, Structure, and Hydrosilylation Catalysis.

When light alkali metal amides [M(Me3 TACD)]n (M=Li, Na, K; (Me3 TACD)H=1,4,7-trimethyl-1,4,7,10-tetraazacyclododecane) were treated with H2 SiPh2 in THF, [M{(H2 SiPh2 )Me3 TACD}(thf)x ] containing a pendant hypervalent dihydridosilicate were formed and characterized by elemental analysis, NMR/IR spectroscopy, and single-crystal X-ray crystallography. The lithium complex catalyzed the hydrosilylation of styrene derivatives under mild conditions with anti-Markovnikov regioselectivity.