UNIGE document Scientific Article
previous document  unige:2849  next document
add to browser collection
Title

The benzodiphosphaalkene ligand and its Pd-II and Pt-II complexes : their synthesis, structure and an ESR study of their reduction products
Authors
Jouaiti, Abdelaziz
Geoffroy, Michel
Terron, Gustavo
Bernardinelli, Gérald Hugues
Published in Journal of the American Chemical Society. 1995, vol. 117, no. 8, p. 2251-2258
Abstract The new diphosphaalkene 1,3-bis[2-(2,4,6-tri-tert-butylphenyl)phosphanediylmethyl]benzenLe,, h as been synthesized. Due to the presence of two P=C bonds three isomers (EE, EZ, ZZ) were observed by 31P NMR, and the crystal structures of two of them could be determined (EE, ZZ). The electrochemical behavior of L has been studied by cyclic voltametry: a quasi-reversible reduction occurs at -1.89 V/SCE and corresponds to the formation of a radical anion which has been studied by ESR at variable temperature. The experimental 31P and 'H hyperfine constants are consistent with free rotation about the P=C and Cphosphaalkene-Cbenzene bonds at room temperature and agree with ab initio predictions. One of the isomers of L forms complexes with palladium(I1) and platinum(I1) ions. The crystal structures show that L is orthometalated and acts as a terdentate ligand by coordinating the metal with each phosphorus atom. These complexes are electrochemically reduced between -0.92 and - 1.29 V, and the resulting paramagnetic species are studied by ESR in liquid and frozen solutions. This reduction process was shown to be a ligand-centered process, an appreciable part of the unpaired electron is localized on each of the phosphaalkene carbons (20%) and phosphorus atoms (5%).
Identifiers
Full text
Other version: http://pubs.acs.org/doi/pdf/10.1021/ja00113a014
Structures
Faculté des sciences / Section de chimie et biochimie / Département de chimie physique
Research group Groupe Geoffroy
Citation
(ISO format) 		JOUAITI, Abdelaziz et al. The benzodiphosphaalkene ligand and its Pd-II and Pt-II complexes : their synthesis, structure and an ESR study of their reduction products. In: Journal of the American Chemical Society, 1995, vol. 117, n° 8, p. 2251-2258. https://archive-ouverte.unige.ch/unige:2849

222 hits

0 download

Contact an author

Update request

Update

Deposited on : 2009-09-21

Export document
Format :
Citation style :