Synthesis and Structures of Alkaline‐Earth Metal Supersilanides: t Bu 3 SiMX and t Bu 3 Si−M−Si t Bu 3 (M = Be, Mg; X = Cl, Br)

The alkaline‐earth metal silanides, ( t Bu 3 Si) 2 Be and ( t Bu 3 Si) 2 Mg, have been synthesized from the reaction of the sodium silanide t Bu 3 SiNa with BeCl 2 in Bu 2 O and MgBr 2 in THF. The bissupersilylmagnesium THF adduct [( t Bu 3 Si) 2 Mg(THF) 2 ] reacts with GaBr 3 in benzene at ambient temperature to form t Bu 3 SiGaBr 2 and t Bu 3 SiMgBr(THF). The structures of bissupersilyl silanides, ( t Bu 3 Si) 2 Be and ( t Bu 3 Si) 2 Mg(THF) 2 , and the Grignard analogue, t Bu 3 SiMgBr(THF), have been determined by X‐ray structure analysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)