Inorganica Chimica Acta [POMAM]

Abstract :

Mononuclear chromium(III) complexes of formula mer-[Cr^IIICl₃(pz*H)₃] (pz*H = pyrazole (pzH), and substituted pyrazoles: 3-Me-pzH, 4-Me-pzH, 4-Cl-pzH, 4-Br-pzH, 4-I-pzH) and trans-[Cr^IIICl₂(pzH)₄]Cl were synthesized from reactions of CrCl₃ hydrate and pyrazole ligands and crystallographically characterized. The fluxional behavior of the complexes, attributed to pyrazole tautomerization, was probed by variable temperature ¹H NMR spectra in the −50 °C to +23 °C range and activation parameters were derived. Q-band EPR were recorded and analyzed for mer-[Cr^IIICl₃(pz*H)₃] (R = H, Me, Cl) showing satellite features corresponding to weak zero-field splitting (zfs).

Graphical abstract:

 

Reference :

Chromium(III)-pyrazole complexes. X-Ray crystal structures, ¹H NMR investigation of ligand fluxional behavior and EPR studies

Jessica M.López Plá, Athanassios K.Boudalis, Joshua Telser, Raphael G.Raptis

Inorganica Chimica Acta, volume 502, 1 March 2020, 119299 - DOI: https://doi.org/10.1016/j.ica.2019.119299

Contact chercheur :

Athanassios K. Boudalis (https://pomam.chimie.unistra.fr/aboudalis/), POMAM, Institut de Chimie (UMR 7177).