Stabilization of Three-Coordinated Germanium(II) and Tin(II) Cations by a Neutral Chelating Ligand

Treatment of the neutral 2-[C(CH3)=N(C6H3-2,6-Pr-i(2))]-6-(CH3O)C6H3N ligand (hereafter assigned as L) with SnCl2 and GeCl2 provided the ionic germanium(II) and tin(II) complexes [(LGeCl)-Cl-II](+)[(GeCl3)-Cl-II](-) (1) and [(LSnCl)-Cl-II](+)[(SnCl3)-Cl-II](-) (2), respectively, as the result of spontaneous dissociation of ECl2 (E = Ge, Sn). The cationic parts [(LECl)-Cl-II](+) of 1 and 2 contain three-coordinated germanium(II) and tin(II) atoms. In comparison, treatment of the ligand L with GeCl4, and SnBr4 yielded the germanium(IV) and tin(IV) complexes LGeCl4 (3) and LSnBr4 (4), respectively, and no dissociation process was observed. Compounds 1-4 were characterized by means of elemental analyses, H-1, C-13, and Sn-119 NMR spectroscopies, and single-crystal X-ray diffraction analysis in (compounds 1 and 4).