Details

Autor(en) / Beteiligte

• Hollóczki, Oldamur
• Wolff, Alexander
• Pallmann, Julia
• Whiteside, Rachel E.
• Hartley, Jennifer
• Grasser, Matthias A.
• Nockemann, Peter
• Brunner, Eike
• Doert, Thomas
• Ruck, Michael

Titel

Spontaneous Substitutions at Phosphorus Trihalides in Imidazolium Halide Ionic Liquids: Grotthuss Diffusion of Anions?

Ist Teil von

• Chemistry : a European journal, 2018-11, Vol.24 (61), p.16323-16331

Ort / Verlag

Germany: Wiley Subscription Services, Inc

Erscheinungsjahr

2018

Quelle

Wiley Online Library

Beschreibungen/Notizen

• PX3 compounds (X=Cl, Br, I) in imidazolium halide ionic liquids combine with the anion Z (Z=Cl, Br, I) of the solvent to form [PX3Z]− complex anions. These anions have a sawhorse shape in which the lone pair of the phosphorus atom fills the third equatorial position of the pseudotrigonal bipyramid. Theoretical results show that this association remains incomplete due to strong hydrogen bonding with the cations of the ionic liquid, which competes with the phosphorus trihalide for interaction with the Z− anion. Temperature‐dependent 31P NMR experiments indicated that the P−Z binding is weaker at higher temperature. Both theory and experiment evidence dynamic exchange of the halide anions at the phosphorus atom, together with continuous switching of the ligands at the phosphorus atom between equatorial and axial positions. Detailed knowledge of the mechanism of the spontaneous exchange of halogen atoms at phosphorus trihalides suggests a way to design novel, highly conducting ionic‐liquid mixtures. Dynamic halide exchange: Phosphorus trihalides PX3 form [PX4]− anions in 1,3‐dialkyl imidazolium halide ionic liquids (HMIM in scheme). The dynamic exchange of the anions at the phosphorus atom shows typical characteristics of a Grotthuss‐like diffusion mechanism and potentially offers a way to design highly conducting materials.