β-Substitution de la méso-tétraphénylporphyrine de zinc par voie électrochimique

Abstract

R e p le 9 ftvrier 1990' ALAIN GIRAUDEAU et LANA EL KAHEF. Can. J. Chem. 69, 1161 (1991). L'oxydation par voie tlectrochimique de la trle'so-tttraphtnylporphyrine de zinc dans des solutions mixtes acttonitrile-dichlorotthane et en prtsence de nucltophiles (Py, 3-Pic, P+,, SCN-) conduit B l'obtention de la mttalloporphyrine correspondante monosubstitute. Pour chacun de ces nucltophiles, la substitution a lieu sur un carbone pyrrolique (P-substitution). Les conditions tlectrochimiques de ces substitutions sont discuttes et nous proposons un bilan global pour cette rtaction de substitution.Mots c l b : porphyrines, rtactions tlectrochimiques, substitutions nucl6ophiles.ALAIN GIRAUDEAU and LANA EL KAHEF. Can. J. Chem. 69, 1161 (1991). The electrochemical oxidation of the zinc tetraphenylporphyrin complex in a mixed acetonitrile-dichloroethane solution in the presence of nucleophiles (Py, 3-Pic, P+,, SCN-) leads to the formation of the corresponding monosubstituted metalloporphyrin. For each of these nucleophiles the substitution occurs at a pyrrole carbon atom (P-substitution). The electrochemical conditions of these substitutions are discussed and an overall reaction is proposed.

Electrochemical reduction of l-(meso-tetraphenylporphyrin)-pyridinium cations

“…The MTPP-b-(4-phenyl-Py + ) molecules (M = H 2 or Zn) were electrochemically synthesised by adapting previously reported procedures [30][31][32]. In the exhaustive electrolysis, 0.1 M TEAPF 6 was employed as supporting electrolyte, as being further removable from the bulk.…”

Survey of Synthetic Routes towards Phosphorus Substituted Porphyrins

“…[13,14] The same phosphonium salt 3 was synthesized by Giraudeau et al from the corresponding electrochemically generated cation radical. [15] In parallel the analogous β-phosphonium salt was obtained from a chemically generated Fe(III)-tetraphenylporphyrin cation radical after treatment with PPh 3 . [16] Through the electrochemical procedure, Giraudeau et al have prepared di-and triporphyrins linked by phosphonium bridges.…”

Electrosynthesis Processes Based on Oxidative Couplings of Porphyrins for the Formation of Supramolecular Assemblies

“…For instance, it has been shown that it was possible to graft triphenylphosphane (PPh 3 ) or thiocyanate (SCN − ) at a β-position of the (TPP)Zn macrocycle, allowing the formation of the monosubstituted [(TPP(PPh 3 ))Zn] + and [(TPP(SCN))Zn] macrocycles, respectively. 84 …”