Rational synthesis of [Ge9{Si(SiMe3)3}3]- from its parent Zintl ion Ge9(4-).

Reported is the first rational synthesis of a trisubstituted deltahedral Zintl ion, [Ge(9){Si(SiMe(3))(3)}(3)](-) in this case, by the addition of the three substituents in a reaction of the parent naked deltahedral Zintl ion Ge(9)(4-) with {(Me(3)Si)(3)Si}Cl. The new species were crystallized and structurally characterized in [K(2,2,2-crypt)](2)[Ge(9){Si(SiMe(3))(3)}(3)] (monoclinic, P2(1)/c, a = 26.497(3) Å, b = 24.090(2) Å, c = 29.268(3) Å, β = 113.888(2)°, V = 17082(3) Å(3), Z = 8, R1/wR2 = 0.0436/0.0812 for the observed data and 0.1023/0.1010 for all data).