Home
Resources
Publications
Speciation of copper(II) Complexes in an Ionic Liquid Based on Choline Chloride and in Choline chloride/water Mixtures

Speciation of copper(II) Complexes in an Ionic Liquid Based on Choline Chloride and in Choline chloride/water Mixtures

Peter De Vreese, Neil R Brooks, Kristof Van Hecke, Luc Van Meervelt, Edward Matthijs, Koen Binnemans, Rik Van Deun

Inorg Chem. 2012 May 7;51(9):4972-81.

PMID: 22524435

Abstract:

A deep-eutectic solvent with the properties of an ionic liquid is formed when choline chloride is mixed with copper(II) chloride dihydrate in a 1:2 molar ratio. EXAFS and UV-vis-near-IR optical absorption spectroscopy have been used to compare the coordination sphere of the cupric ion in this ionic liquid with that of the cupric ion in solutions of 0.1 M of CuCl(2)·2H(2)O in solvents with varying molar ratios of choline chloride and water. The EXAFS data show that species with three chloride ions and one water molecule coordinated to the cupric ion as well as species with two chloride molecules and two water molecules coordinated to the cupric ion are present in the ionic liquid. On the other hand, a fully hydrated copper(II) ion is formed in an aqueous solution free of choline chloride, and the tetrachlorocuprate(II) complex forms in aqueous choline chloride solutions with more than 50 wt % of choline chloride. In solutions with between 0 and 50 wt % of choline chloride, mixed chloro-aquo complexes occur. Upon standing at room temperature, crystals of CuCl(2)·2H(2)O and of Cu(choline)Cl(3) formed in the ionic liquid. Cu(choline)Cl(3) is the first example of a choline cation coordinating to a transition-metal ion. Crystals of [choline](3)[CuCl(4)][Cl] and of [choline](4)[Cu(4)Cl(10)O] were also synthesized from molecular or ionic liquid solvents, and their crystal structures were determined.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP10125130	Copper(II) chloride dihydrate		10125-13-0	Price
AP67481-A	Choline chloride		67-48-1	Price

As a specialist in analytical chemical Products, Alfa Chemistry offers consumers a wealth of raw materials and a full range of technologies and services.

QUICK LINKS

HEADQUARTERS

Tel:

Fax:

Email: