Cyclische Diazastannylene. - XXX : Symmetrisch und asymmetrisch substituierte German- und Stannandiyle mit Amid-, Alkoholat- und Thiolat-Liganden. - Teil I

M. V eith*. P. H obein und R. R osier Institut für Anorganische Chemie der Universität des Saarlandes, D-6600 Saarbrücken Z. Naturforsch. 44b, 1067—1081 (1989); eingegangen am 2. März 1989 Syntheses, X-Ray, Symmetrically and Unsymmetrically Substituted Germaneand Stannanediyls, Chelates of G e(II) and Sn(II) Symmetrically and unsymmetrically substituted germaneand stannanediyls as well as che lated bis(amino)or aminooxogermaniumand -tinmonohalides have been obtained from cyclic bis(amino)germaneand stannanediyls by treatment with /m -butylam ine, fm -butanol and rm -butylm ercaptane. The following compounds have been svnthesized; GeX^ (X = OrBu (5), SrBu (6)), Sn(SrBu), (9), GeXCl (X = N(H)rBu (21), Ö/Bu (22)), SnXCl (X = N(H)rBu (23), O/Bu (24), S/Bu (25), OMe (28)) and Sn(OzBu)Br (27). In the series of the chelates Me2Si(NrBu)(NH/Bu)GeCl (13), Me2Si(N?Bu)(OrBu)SnX (X = Cl (18). OMe (19)) and the bischelate [Me2Si(N?Bu)(0/Bu)]2Sn (20) have been prepared. When 18 is allowed to react with aluminiumtrimethyl Me2Si(N;Bu)(OrBu)AlClMe is formed, a compound with a center of chirality at ine aluminium atom. X-ray structure determinations have been performed on single crystals of 6, 8, 9, 13, 22 and 24. 6, 8, 22 and 24 form molecular dimers with c.n. of 3 at the Ge or Sn atoms, resp. While the /Bu —S ligands are syn with respect to the central G e2S2 ring in 6 (symmetry approaching C2v). the fBu — O ligands are anti to the central Sn20 2 ring in 8 (sym metry C|). 9 forms a coordination polymer with all Sn atoms in a i^-trigonal-bipyramidal and all S atoms in a i/'-tetrahedral environment. The germanium atom in 13 is coordinated by a chlorine, a A3and a A4-nitrogen atom , the two nitrogen atoms being connected by as dimethylsilyl group. The hydrogen and chlorine atom of 13 are found at the same side of the four-membered chelate ring. The two unsymmetrically substituted, homologous compounds G e(0/B u)C l (22) and Sn(OrBu)Cl (24) are found to form dimers via O—>Ge resp. O-^Sn bonds. While the chlorine atoms in 22 are syn with respect to the four-membered ring, they are anti in the case of molecule 24.