Soline Sibille

Electrosynthesis of alcohols from organic halides and ketones or aldehydes

Abstract The electrosynthesis of a wide range of alcohols from organic halides and ketones or aldehydes is achieved under simple and mild conditions in an undivided electrolytic cell using different sacrificial anodes.

Catalyse par des complexs σ-aryl-nickel de l'electroreduction en biaryles des halogenures aromatiques

Abstract In mixed THF/HPMA, electrochemical reduction of NiX 2 L 2 (L = PPh 3 , X = Cl or Br) yields a zerovalent nickel complex which reacts very rapidly with ArX (X = I, Br, Cl) by oxidative addition to give ArNiXL 2 , which also is electroreducible. Thus it is possible to obtain a catalytic electroreduction of ArX which affords mainly biaryls when X = Cl. A mechanism is suggested according the various results especially with a view to explain the loss of catalytic activity. A clear indication of increasing activity is given when aliphatic bromides are added to the solutions.

Electroreductive coupling of trifluoromethylarenes with electrophiles: synthetic applications

The electroreductive coupling of trifluoromethylarenes with carbon dioxide, acetone, or N,N-dimethylformamide is achieved with good yields by electrolysis in an undivided cell fitted with a sacrificial anode.

Electrosynthesis of ketones from organic halides and anhydrides

Abstract The electroreduction of benzylic and allylic halides in the presence of anhydrides affords ketones in moderate to good yields. The electrolysis is performed in an undivided cell, under constant current, using an aluminium or magnesium anode.

Oxydation électrochimique des aldéhydes en solution aqueuse: I. Oxydation de solutions aqueuses basiques d'aldéhydes à des électrodes d'or et de platine

Abstract Voltemmetric experiments have been performed upon 9 aldehydes in aqueous basic solutions from pH 9 to pH 14, at rotating gold and platinum electrodes. The potential of the first oxidation process, which is either a wave or a peak, depends linearly on pH. It is identical for all the studied aldehydes but differs at both electrodes. From the relation between the maximal intensity and pH, it can be concluded that the electroactive species is in all cases the geminal diol anion RCHOHO − . In order to explain all the experimental results we propose the following assumption: aldehyde oxidation proceeds from a chemical reaction between adsorbed monoionized aldehyde hydrate and superficial metal oxides.

Electroreductive coupling of methallylchloride or methyl chloroacetate with carbonyl compounds catalyzed by nickel bipyridine complexes

Abstract An efficient electrosynthesis of homoallyl alcohols or β-hydroxy esters in the presence of catalytic amounts of the NiBr 2 (2,2′-bipyridine) complex has been developped from mixed electrolysis of methallylchloride, or methylchloroacetate with several carbonyl compounds, using a one-compartment cell equiped of a sacrificial zinc anode.

Olefin dimerization by electrogenerated nickel(I)-phosphine complexes

Abstract In propylene carbonate, electroreduction of Ni2+—PPh3—C2H4 mixtures affords a Ni(I) complex able to dimerize ethylene at room temperature under atmospheric pressure, mainly to 2-butenes. Starting from NiCl2-(PPh3)2, electrolysis in a one-compartment cell with a suitable sacrificial anode (Zn, Cd, Al) also initiates the dimerization-isomerization process of ethylene and propylene.

A Facile Synthesis of Trifluoroacetaldehyde by Electroreduction Of Cf3Br In Dimethylformamide

Abstract Trifluoroacetaldehyde, isolated as CF3CH(OCOCH3)2, is obtained in high yield by electroreduction of CF3Br in DMF, using an undivided cell and a sacrificial aluminium anode.

Nickel-catalysed electroreductive coupling of α-halogenoesters with aryl or vinyl halides

β, γ-Unsaturated esters are obtained in moderate to good yields by a one-step electrochemical procedure from α-chloroesters and aryl or vinyl halides; a sacrificial aluminium anode, dimethylformamide as solvent, and a catalytic amount of nickel bromide-2,2′-bipyridine complex are used.