Diamidophosphine as a Precursor of the Iminophosphonamidinate Ligand in the Yttrium Complex

Diamidophosphine t BuP(NHMes) 2 (H 2 L) is synthesized by the treatment of t BuPCl 2 with two equivalents of KNHMes (Mes is 2,4,6-Me 3 C 6 H 2 ). The reaction of H 2 L with potassium hydride in THF (THF is tetrahydrofuran) affords the anionic form HL − with the hydrogen atom migrating from nitrogen to phosphorus, which is confirmed by the 1 H and 31 P NMR data. The structure of the formed iminophosphonamidinate anion HL − is determined by X-ray diffraction (XRD) in the crystalline phase of K[K(THF) 2 ]( t BuPH(NMes) 2 ) 2 ∙C 7 H 8 (KHL). The reaction of KHL with yttrium chloride gives complex [Y( t BuPH(NMes) 2 ) 2 Cl] ([Y(HL) 2 Cl]) in which, according to the XRD data, ligands HL − are in the iminophosphonamidinate PH form. The 1 H and 31 P NMR spectra confirm that this structure of the complex exists in the solution.