Synthesis and Characterization of a New Series of Nickel(II) meso-Tetrakis (polyfluorophenyl)porphyrins Functionalized by Pyrrole Groups and Their Electropolymerized Films.
A new series of nickel(II) meso-tetrakis(polyfluorophenyl)porphyrins functionalized by pyrrole groups have been synthesized. Each new complex was isolated and characterized by (1)H NMR, (19)F NMR, IR, UV-visible spectroscopy, and mass spectrometry as well as electrochemistry. This is the first example of polyfluorinated substituted porphyrins where the four possible compounds have been obtained by functionalization of the para-fluorine substituents of the nickel(II) meso-tetrakis(pentafluorophenyl)porphyrin. This functionalization has allowed the preparation for the first time of polyfluorinated metalloporphyrin films by oxidative electropolymerization. Electrochemical stability studies of these polymeric films have shown better stability for films derived from the monomer having four pyrrole groups because of their high degree of cross-linking degree. A large difference of electroactive solute permeation has been found in the polymeric films which have been obtained by electropolymerization of monomers for which one pyrrole group has been substituted compared to those for which four pyrrole groups have been substituted. This could be related to quite rigid polymer structures for tetrasubstituted polymer films and molecular sieving properties of monosubstituted polymer films. The spectroelectrochemistry of a polymeric film on an OTE has established that the two-electron-oxidized species are stable in the film; likewise the singly and doubly electroreduced species are stable and are more likely ligand-centered.
Carvalho De Medeiros
Maria A.
MA
Laboratoire d'Electrochimie Organique et de Photochimie Rédox (URA CNRS 1210), Université Joseph Fourier Grenoble 1, BP 53, 38041 Grenoble Cedex 9, France.
Cosnier
Serge
S
Deronzier
Alain
A
Moutet
Jean-Claude
JC