Tr. Van Den Ancker et al., Hypervalent silicon via intramolecular coordination in a four-membered ring in complexes of substituted pyridyl ligands, ORGANOMETAL, 19(22), 2000, pp. 4437-4444
Reaction of SiXnCl4-n (X = H, Me) with "Li(C(SiMe3)(2)( 2-C5H4N))" or "Li(C
(SiMe3)(2)(6-Me-2-C5H3N))" yields hypervalent five-coordinate compounds, es
tablished in the solid state for SiRHCl2 (5 and 7), which show strong intra
molecular Si-N interactions in the four-membered chelate ring (NSiC2) that
persist in solution (Si-N = 2.066(9) and 2.072(4) Angstrom, X = H). Complex
es based on HCPh2(2-C5H4N) form four-coordinate species, whereas complexes
based on HCPh(SiMe3)(2-C5H4N) afford either four- or five-coordinate comple
xes; the rac isomers of Si(CH(SiMe3)(2-C5H4N))(2)MenCl2-n (26 and 27), form
ed stereospecifically, are four-coordinate.