Abstract
The compound (Me
3Si)
2CCl
2 was converted by treatment with BuLi/Et
2O/THF and then with Me
2HSiCl into (Me
3Si
2)CCl(SiMe
2H). Further lithiation with BuLi gave LiC(SiMe
3)
2(SiMe
2H), which reacted with ZnBr
2 to yield Zn[C(SiMe
3)
2(SiMe
2H)]
2. Thence, several new organozinc compounds Zn[C(SiMe
3)
2(SiMe
2X)]
2, with X Cl, Br, I, F, OH, OMe, O
2CCF
3, O
2CH, or NCS, were obtained by substitutions at silicon without cleavage of ZnC bonds. The compounds Cd[C(SiMe
3)
2(SiMe
2X)]
2, with X H, OMe, and Ph, were obtained similarly, but subsequent substitutions at Si were accompanied by reactions at Cd. The crystal structure of the trifluoroacetato derivative Zn[C(SiMe
3)
2(SiMe
2 OCOCF
3)]
2 shows that the molecules are centrosymmetric, with the O
2CCF
3 groups forced outwards by steric hindrance away from the metal centre. In Cd[C(SiMe
3)
2(SiMe
2OMe)]
2, the methoxy groups are folded in towards cadmium but the Cd … O distance is only slightly shorter than the sum of the van der Waals radii.