Synthetic and structural investigations of alkali metal diamine bis(phenolate) complexes

摘要

Two lithium and one sodium diamine bis(phenolate) complexes have been prepared and characterised by X-ray crystallography and NMR spectroscopy. Two parent diamine bis(phenol) ligands were utilised in the study (1-H-2 and 2-H-2). Dimeric (1-Li-2)(2) was prepared by treating 1-H-2 with two molar equivalents of n-butyllithium in hydrocarbon solvent. It adopts a ladder-like structure in the solid state, which appears to deaggregate in C6D6 solution. The monomeric (hence, dinuclear) TMEDA-solvated species [2-Li-2 center dot(TMEDA)] has two chemically unique Li atoms in the solid state and is prepared by reacting 2-H-2 with two molar equivalents of n-butyllithium in hydrocarbon solvent, in the presence of N,N,N',N'- tetramethylethylenediamine (TMEDA). Finally, the dimeric sodium-based [2-Na-2 center dot(OEt2)](2) was prepared by reacting 2-H-2 with two molar equivalents of freshly prepared n-butylsodium in a hydrocarbon-diethyl ether medium. The complex adopts a Na4O4 cuboidal structure in the solid state, which appears to remain intact in C6D6 solution.