Alkali-metal complexes with tris(2-diphenylphosphorylethyl)amine. Crystal structures of [Li2{N(CH2CH2POPh2)3}2][Li{N(CH2CH2POPh2)3}]2[BPh4]4 and [Na{N(CH2CH2POPh2)3}(H2O)(BuOH)]BPh4

Abstract

By oxidation of N(CH₂CH₂PPh₂)₃ with H₂O₂ the ligand N(CH₂CH₂POPh₂)₃·3H₂O was synthesized. In CH₂Cl₂ with MBPh₄ in butanol, where M = Li or Na, the new ligand gives complexes of formula [Li₂{N(CH₂CH₂POPh₂)₃}₂][Li{N(CH₂CH₂POPh₂)₃}]₂[BPh₄]₄, (1), and [Na{N(CH₂CH₂POPh₂)₃}(H₂O)(BuOH)] BPh₄, (2). The crystal structures of these compounds have been determined from counter diffraction data: (1), triclinic, space group P, a= 19.958(11), b= 17.767(9), c= 17.880(9)Å, α= 87.63(8), β= 64.38(8), γ= 86.25(8)°, and Z= 1; (2), triclinic, space group P, a= 16.958(9), b= 14.341(8), c= 14.200(8)Å, α= 97.39(8), β= 109.43(9), γ= 94.78(8)°, and Z= 2. The structure of (1) consists of two distinct complex cations, in which the lithium atom exhibits different environments, tetrahedral and trigonal respectively. In (2) the sodium atom is surrounded in a tetrahedral fashion by two oxygen atoms of the phosphine ligand, and by the oxygen atoms of one water and one butanol molecule.