Germanium-, Tin-, Lead-, and Bismuth-Containing <i>β</i>-Diketiminato Complexes for the Synthesis and Structural Characterization of Hydroxide, Carboxylic Acid, Heterobimetallic Oxide, Transition Metal-Main Group, Hydride and Halide Compounds

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In the present work, some aspects of the chemistry of heavier low-valent Group 14 and Group 15 elements bearing β-diketiminato ligands are investigated, and the new compounds are characterized by elemental analysis, spectrometric and spectroscopic methods, as well as single crystal X-ray structural analysis. Moreover, the electronic attributes of some of the compounds are studied by density functional theory calculations. A novel synthetic approach (hydrolysis in the presence of Arduengo-type carbene as HCl acceptor) is successfully introduced for the preparation of LGeOH (L = HC[(CMeNAr)]2, Ar = 2,6-iPr2C6H3), the first example of a Group 14 element hydroxide in oxidation state (II). The chemical reactivity of the lone pair of electrons at the germanium atom in the β-diketiminatogermanium(II) hydroxide is on the one hand first reacted with chalcogens to give an unprecedented LGe(S)OH and LGe(Se)OH compounds, and on the other hand with transition metal fragments to lead to the formation of hetererobimetallic LGe(OH)M systems (M = Fe, Mn). In the case of the germanium analogues of a thio- and selenocarboxylic acid, the acid strength (pKa) is determined by theoretical calculations. Furthermore, the OH functionality of the LGeOH compound results in the novel heterobimetallic LGe(µ-O)M(Me)Cp (M = Zr, Hf) oxides by the hydrogen abstraction from the hydroxyl group with metallocene-dimethyl derivatives of Group 4. It is for the first time synthesizes and structurally characterizes monomeric terminal germanium(II) and tin(II) hydrides LGeH and LSnH. Both compounds are prepared in good yield by reacting β-diketiminatogermanium(II) or β-diketiminatotin(II) chlorides with AlH3 NMe3. For the β-diketiminatotin(II) hydride, the Sn H resonance is the lowest-field chemical shift observed for a tin hydrides. In addition, salt elimination reactions of the corresponding β-diketiminatolead(II) and β-diketiminatobismuth(III) lithium salts with lead and bismuth halides result in the isolation of novel β-diketiminatolead(II) bromide and β-diketiminatobismuth(III) chloride LPbBr and L´BiCl2 (L´= HC(Et2NCH2CH2NCMe)2).