Synthesis and Crystal Structure of the Tetraaluminatetrahedrane Al4[Si(t-Bu)3]4, the Second Al4R4 Compound

The reaction of (AlI·NEt 3 ) 4 with donor-free t- Bu 3 SiNa in toluene at −78 °C leads to the generation and crystallization of Al 4 [Si( t- Bu) 3 ] 4, which after Al 4 Cp* 4 is the second structurally characterized Al 4 R 4 compound. The obtained experimental data were compared with results of ab initio calculations.