Synthesis and solid-state crystal structure of [2-(diphenylphosphinoyl)ethyl]diethylammonium dichlorocuprate(I), containing a discrete CuCl2– anion

Abstract

[2-(Diphenylphosphino)ethyl]diethylamine, reacts with copper(II) chloride in ethanol or tetrahydrofuran to yield either [2-(diphenylphosphinoyl)ethyl]diethylammonium dichlorocuprate(I)(IV), or [2-(diphenylphosphino)ethyl]-diethylammonium dichlorocuprate(I)(III). Compound (IV) has been characterized by measurements of conductivity, magnetic susceptibility, and i.r. and u.v. spectra. Water in the solvents is apparently the source of both the proton and the oxygen atom required for formation of (IV). A three-dimensional X-ray structural analysis of (IV) was also undertaken. Crystals from either solvent are monoclinic, space group P2₁/c, a= 12·54(1), b= 9·119(8), c= 21·73(1)Å, β= 123·10 (5)°, and Z= 4. The structure was solved by a combination of the symbolic-addition and heavy-atom procedures and refined by least squares to R 11·0% for 2661 visually estimated observed reflections. The structure consists of discrete cations and [CuCl₂^–] anions whose closest approach is Cu ⋯ O 3·74 Å; the anion is near-linear, Cu–Cl 2·090(5)Å, Cl–Cu–Cl 175·8(2)°.