Influence of the ring atoms on the structure of triel-pentel heterocycles synthesis and X-ray crystal structures of [Me2InAs(SiMe3)(2)](2) and [Me2InSb(SiMe3)(2)](3) [German]

摘要

Triel-pentel heterocycles [Me2InE(SiMe3)(2)](x) have been prepared by dehalosilylation reactions from Me2InCl and E(SiMe3)(3) (E = As, x = 2; E = Sb, x = 3) and characterised by NMR spectroscopy and by X-ray crystal structure analyses. In addition the X-ray crystal structures of [Me2GaAs(SiMe3)(2)](2) and [Me2InP(SiMe3)(2)](2) are reported. The compounds complete a family of 13 identically substituted heterocycles [Me2ME(SiMe3)(2)](x) (M = Al, Ga, In, E = N, P, As, Sb, Bi; x = 2, 3), whose structures were investigated depending on the ring atoms M and E. The tendencies that have been observed concerning the ring sizes: can be explained by the interplay of the atomic radii of the central atoms and the sterical demand of the ligands. After a formal separation of the M-E bonds in sigma bonds and dative bonds the characteristic differences and trends in the endocyclic and exocyclic bond angles of both centres M and E can be interpreted on the basis of a simple Lewis acid/base adduct model. [References: 27]