Ate complexes of Ge(II) and Sn(II) with bidentate ligands [LiE14(OCH2CH2NMe2)3]2 (E14=Ge, Sn): synthesis and structure

The reaction of equimolar quantities of LiOCH2CH2NMe2 and E14(OCH2CH2NMe2)2 (E14=Ge, Sn) in ether yielded new ate complexes [LiE14(OCH2CH2NMe2)3]2 (E14=Ge (1), Sn (2)) with bidentate ligands. The compounds 1 and 2 are white crystalline substances which are highly soluble in THF and pyridine and very sensitive to the traces of oxygen and moisture. The structures of these compounds are studied by X-ray diffraction analysis. The ate complexes 1 and 2 are powerful nucleophiles and may be employed as ligands (neutral) in the coordination chemistry of the transition metals. The electronegative O-substituents at the divalent E14 atoms render them less oxidizable than alkyl- or aryl-substituted derivatives, and the bidentate ligands, owing to intramolecular donor–acceptor interactions, make them more thermodynamically stable compared to monodentate ligands.