Synthesis and Characterization of Ge(II), Sn(II), and Pb(II) Monoamides with −NH2 Ligands
datasetposted on 18.04.2005, 00:00 by Corneliu Stanciu, Shirley S. Hino, Matthias Stender, Anne F. Richards, Marilyn M. Olmstead, Philip P. Power
The synthesis and characterization of the first divalent germanium, tin, and lead monoamide derivatives of the parent amide group −NH2 are presented. They have the general formula (ArMNH2)2 (M = Ge, Ar = Ar‘ (C6H3-2,6-Pri2) or Ar* (C6H3-2,6(C6H2-2,4,6-Pri3)); M = Sn, Ar = Ar*; M = Pb, Ar = Ar*). For germanium and tin, they were obtained by reacting the corresponding terphenyl halides of the group 14 elements with liquid ammonia in diethyl ether. The lead amide derivative (Ar*PbNH2)2 was synthesized by reaction of LiNH2 with Ar*PbBr in diethyl ether. The compounds were characterized by IR and multinuclear NMR spectroscopies and by X-ray crystallography in the case of the (Ar‘GeNH2)2 or (Ar*SnNH2)2 derivatives. They possess dimeric structures with two −NH2 groups bridging the germanium and tin centers. For lead, the reaction with ammonia led to isolation of a stable ammine complex of formula Ar*PbBr(NH3) which was characterized by IR and NMR spectroscopies and by X-ray crystallography. It is the first structural characterization of a divalent lead ammine complex.