Tetrylenes chelated by bifunctional β‐diketiminate ligand: structure and possible applications

Abstract

The synthesis and structure of heteroleptic tetrylenes containing bifunctional β‐diketiminate ligand are reported. Compounds were prepared via a protolytic reaction of free β‐diketimine {N‐[(2‐MeO)C6H5]}N═C(Me)CH═C(Me)N(H){N′‐[(2‐MeO)C6H5]} (LCOH) and {N‐[(2‐MeO)C6H5]}NCHCHCHN(H){N′‐[(2‐MeO)C6H5]} (LHOH), respectively, with corresponding bis(amide) – M[N(SiMe3)2]2 (M = Ge, Sn, Pb) – in equimolar ratio or via the salt elimination route from lithium precursors generated from LHOH/LCOH species and slight excess of SnCl2 or GeCl2.dioxane complex. Only heteroleptic complexes were obtained by the mentioned methods. Products were characterized by multinuclear NMR spectroscopy techniques and structures of four of them have been determined by X‐ray diffraction methods. Complexes LHOGeCl and LCOSnN(SiMe3)2 crystallize as monomers with the three‐coordinated metal centres by one chloro or amido ligand and one bidentate β‐diketiminato unit, in contrast to the structure of LCOSnCl, which reveals a dimeric character and compound LCOPbN(SiMe3)2, where the central atom of lead is five‐coordinated by methoxy groups of the ligand. Complex LCOSnN(SiMe3)2 was tested as a catalyst for polymerization of various epoxides. Copyright © 2014 John Wiley & Sons, Ltd.