An Electrochemical Study of Bis(cyclopentadienyl)titanium(IV) Dichloride in the Presence of Magnesium Ions, Amides or Alkynes

 Abdou K. D. Dimé Abdou K. D. Dimé , Yvan Six Yvan Six , Olivier Buriez Olivier Buriez
Russian Journal of Electrochemistry
Abstract / Full Text

In tetrahydrofuran, the electrochemical reduction of Cp2TiIVCl2 (2 mM) generated three titanium(III) complexes which were in equilibrium: [Cp2TiCl2]•−, [Cp2TiCl] and (Cp2TiCl)2. Although the anion radical [Cp2TiCl2]•− was the main species produced under these conditions, cyclic voltammetry investigations clearly showed that the proportion of the three electrogenerated TiIII complexes can be modified as a function of the amounts of chloride ion present in the solution. Accordingly, the presence of Mg2+ ions, which led to the consumption of chloride ions through the formation of MgCl2, favoured the formation of [Cp2TiCl] and, consequently, of the corresponding dimer (Cp2TiCl)2. The electrochemical behaviours of Cp2TiIVCl2 and of the electrogenerated low-valent Ti complexes were also investigated in the presence of amide and alkyne derivatives. Under these conditions, titanium complexes could not only interact with the amide carbonyl group, but also with the alkyne triple bond, provided the latter was not sterically hindered. Interestingly, the carbonyl group and the triple bond had antagonist effects on redox properties of titanium(III) complexes.

Author information
  • Equipe Matériaux, Electrochimie et Photochimie Analytiques (EMEPA) de l’Université Alioune Diop de Bambey, B.P. 30, Bambey, Sénégal

    Abdou K. D. Dimé

  • Laboratoire de Synthèse Organique (LSO), UMR 7652 CNRS / ENSTA / École Polytechnique, Institut Polytechnique de Paris, 91128, Palaiseau Cedex, France

    Yvan Six

  • PASTEUR, Département de Chimie, Ecole Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005, Paris, France

    Olivier Buriez

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