NOVEL CHELATED DIORGANOLITHATE ION IME(2)C(SIME(3))(2)LIC(SIME(3))(2)SIME(2)CH(2)](-) AND HIGHLY CROWDED CHELATED ORGANOMERCURY COMPOUND 2)SIME(2)C(SIME(3))(2)HGC(SIME(3))(2)SIME(2)CH(2)]

The compound {(Me(3)Si)(2)CHSiMe(2)CH(2)}(2) has been prepared and met alated with MeLi to give the chelated lithate ion Me(2)C(SiMe(3))(2)Li C(SiMe(3))(2)SiMe(2)CH(2)](-), which was isolated as its [Li(TMEDA)(2) ] salt (TMEDA = N,N,N',N'-tetramethylethylenediamine). The potential o f this salt as a source of the very bulky dicarbanionic ligand {(Me(3) Si)(2) (C) over bar SiMe(2)CH(2)}(2) was demonstrated by its reaction with HgBr2 in THF to give the chelated mercury compound )SiMe(2)C(SiMe (3))(2)HgC(SiMe(3))(2)SiMe(2)CH(2)]. The crystal structures of the sal t and the mercurial compound were determined.