Claude Moinet

Electrochemical reduction of η5-cyclopentadienyl Fe+ η6-arene cations in basic media: Study of the behaviour “in situ” of the corresponding radicals

Abstract The one-electron reversible electroreduction of η 5 -cyclopentadienyl iron η 6 -arene cations on mercury in basic media provides the radicals ⋆⋆ of same formula. The behaviour of these radicals [catalysis, decomposition liberating Fe(0) or Fe(II) or dimerization] depends on the nature and on the number of the substitutents on the rings and also on the medium (aqueous, alcohol aqueous, alcohol). These results are explained in terms of the stability and solubility of the intermediates.

Biomass conversion II: simultaneous electrosyntheses of furoic acid and furfuryl alcohol on modified graphite felt electrodes☆

Simultaneous electrocatalytic production of furoic acid and furfuryl alcohol from furfural is performed on modified graphite felt electrodes in aqueous electrolyte using a separated flow cell.

Mécanisme de réduction des mononitrobenzènes en milieu aqueux: Formation des produits secondaires lors des électrolyses

Abstract In acidic solutions, the cathodic reduction of substituted mononitrobenzenes involves the non-reducible intermediary N,N-dihydroxylphenylamine (Ar-N(OH)2). During the macroelectrolysis, the nitrosobenzenes formed by dehydration of the dihydroxylamines couple with the phenylhydroxylamines (Ar-NHOH); the resulting azoxy compounds precipitate or are reduced to the corresponding azo or hydrazo derivatives.

2-Substituted indazoles from electrogenerated ortho-nitrosobenzylamines

Abstract An electrochemical methodology for an efficient access to ortho -nitrosobenzylamines has been developed. These products cyclize intramolecularly producing the desired 2-substituted indazoles in high yields. The electrochemical procedure overcomes limitations of previous chemical methods.

Mecanisme e.c.e. de reduction du para-dinitrobenzene en para-nitrophenyhydroxylamine

In acidic solutions, at low temperature, the first cathodic reduction of p-dinitrobenzene involves the intermediate N-p-nitrophenyl-N,N-dihydroxyamine (O2NC6H4N(OH)2). The dehydration of this dihydroxyamine leads to the p-nitrosonitrobenzene (O2NC6H4NO) which is reduced to the N-p-nitrophenylhydroxylamine (O2NC6H4NHOH). The interposed chemical reaction of this e.c.e. mechanism involves acid-base catalysis.

Cyclic voltammetry and XPS analyses of graphite felt derivatized by non-Kolbe reactions in aqueous media

This present work describes a preliminary study of modification of graphite felt for future applications in indirect electrolysis. The anodic oxidation of electroactive carboxylate compounds was achieved in aqueous media. The derivatization of the electrode was highlighted by cyclic voltammetry and XPS analyses. Interestingly, the grafting process led to chemically stable covalent attachment of nitroaryl species on the graphite felt with simultaneous increase of its real surface area. The comparison with the process performed in acetonitrile underlines the role of graphite oxidation in the immobilization of the molecules on the felt.

Covalent attachment of TEMPO onto a graphite felt electrode and application in electrocatalysis

This work describes a simple method to attach TEMPO by an amide link to a graphite felt electrode. The derivatization of the electrode is highlighted by cyclic voltammetry and XPS analyses. Cyclic voltammetry analyses showed the catalytic activity of the grafted TEMPO in both organic and aqueous media. The electrolyses revealed improved stability of the grafted catalyst in aqueous medium compared to acetonitrile. Furthermore, the catalyst is more stable when it is immobilized onto the electrode than when it is in homogeneous solution. The XPS analyses of the grafted felt after electrocatalysis in aqueous medium shows that the degradation of the modified electrode during the electrolysis is not due to a break of the amide link between the graphite felt and TEMPO.

Anodic cyanation of (-)-N-phenyl-2-methylpiperidine: A short synthesis of (+)-solenopsin A and (+)-isosolenopsin A

Abstract A convenient method for the preparation of (+)‐Solenopsin A 1 (5 steps, 21%) involving regiospecific anodic cyanation of (−)‐N‐phenyl‐2‐methylpiperidine 4 is described.

Reactivity of carbanions of Fischer-type carbene complexes with pyrylium salts. Synthesis and characterization of new γ-methylenepyran carbene complexes via an addition–oxidation–deprotonation process

The condensation reaction between γ-unsubstituted pyrylium salts and carbanions of Fischer-type carbene complexes allowed the synthesis of new γ-methylenepyran carbene complexes. NMR data, single crystal X-ray analysis, and DFT calculations suggest that these complexes have a partial pyrylium character due to the π electron-accepting ability of the carbenic fragment and to the electron-releasing properties of the methylenepyran part.

Cationic (η5-cyclopentadienyl)(η6-arene)iron(II) catalyst for the electroreduction of nitrate ion

The 19-electron complex radicals resulting from the one-electron reduction of the cationic precursors [(η5-cyclopentadienyl)(η6-arene)FeII]+ quickly reduce nitrate ions to ammonia in aqueous solutions.