Group 1 elements amido complexes

Two principle strategies have been employed for the synthesis of siloxide-containing molecular precursors. The first involves a silanolysis, or condensation, reaction of the Si - OH groups with a metal amido, alkyl, hahde, or alkoxide complex. The second method involves salt metathesis reactions of an alkali metal siloxide with a metal hahde. Much of our work has been focused on formation of tris(tert-butoxy)siloxide derivatives of the early transition metals and main group elements. The largely imexplored regions of the periodic table include the lanthanides and later transition metals. 

The primary amides of the group 2 elements, M(NH2)2, are nonmolecular species. " When the NH2 ligand is replaced by the bulky bis(trimethylsilyl)amido group, however, molecular complexes are formed. A complete set of structures has been obtained for Be through Ba (Table 11). The barium bis(trimethylsilyl)amides form a progression of compounds that illustrate the important relationship between ligand bulk and metal nuclearity. The base-free compound, [Ba N(SiMe3)2 ]2, exists as a dimer that can accommodate... 

Miscellaneous ligands so far incorporated into the polystyrene matrix include imidazolyl [21], 2-amido oxime [22], thioether and sulfoxide moieties [23]. The procedure is simple and essentially involves the halogen-replacement of Cl- or Br- from polystyrene matrix, bearing CH2C1, or Br- groups. Mostly, first row transition element salts undergo facile complexation with these modified polystyrene matrices [21] (Fig. 11). 

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