Jean-Claude Folest

Electrocatalyzed carboxylation of organic halides by a cobalt-salen complex

The carboxylation of benzylic and allylic chlorides by CO2 in tetrahydrofuran + hexamethylphosphoramide (40% – 60%) is electrocatalyzed by a cobalt Schiff-base complex Co(Salen). The reactions were performed by controlled-potential electrolysis at the RCo (Salen) reduction potential. The yield of the carboxylic acid formation has been calculated.

Etude electrochimique de complexes derives de l'ethylene bis(salicylidene iminato)cobalt; application a la reduction electroassistee d'halogenures organiques

Abstract Electrocatalyzed reduction of organic halides with ethylenebis(salicylideneiminato)cobalt (CoSalen) in THF/HMPT ( 40 60 ) at 25°C is studied. The kinetics of formation and cleavage of CoC bonds is analyzed by cyclic voltammetry at a gold electrode of CoSalen in the presence of RX (RX = n-C4H9Br, n-C7H15Cl, C6H5CH2Cl, C6H5CHCHCH2Cl, CH3CHCHCH2Cl, C6H5I C6H5CHCHBr). Quantitative reductions at controlled potential on a mercury pool are performed with RCl or RBr or with mixtures of halides RX + R′X in the presence of CoSalen. The yield of the products obtained is determined and the conditions for CC bond formation by homocoupling (RR formation) or heterocoupling (RR′ formation) are optimized.

Electrochemical Synthesis of Trifluoromethane Sulfinic Acid Salt From CF3Br and SO2

Abstract The electroreduction of a mixture of SO2 and CF3Br in DMF, in an undivided cell with a soluble anode (Mg or Zn) lead to salt of trifluoromethane sulfinic acid in high yield.

Electrochemical synthesis of ketones from acid chlorides and alkyl and aryl halides catalysed by nickel complexes

Abstract The nickel-catalysed electrochemical cross-coupling of acid chlorides and alkyl or aryl halides in acetonitrile affords unsymmetric ketones in good to high yields. The reaction can be performed under very simple and mild conditions in a diaphragmless cell. A zinc rod as the sacrificial anode has been found to be the most efficient.

Catalyse chimique par le systeme nickel-2,2′-bipyridine de la reduction electrochimique d'halogenures aliphatiques

Abstract In dimethylformamide or N -methylpyrrolidone the Ni-bipyridyl system catalyses the electrochemical reduction of functionalised or non-functionalised aliphatic halides. High yields of dimeric products are obtained besides primary mono- or di-bromides. Analysis of the reaction products shows the formation of dialkylnickel which can be isolated by coulometry. This species acts as a reducing agent for aliphatic halides.

Electrochemical synthesis of tertiary phosphine from organic halides and chlorophosphines

Abstract The electrochemical synthesis of a wide range of tertiary mono- and diphosphines has been achieved in very simple and mild conditions, in an undivided electrolytic cell with a sacrificial anode of magnesium.

Electrochemical cross-coupling of organic halides: Trichloromethylation and related synthesis of gem-dichloro compounds

Abstract The cross-coupling of activated alkyl halides with carbon tetrachloride or substituted trichloromethanes can be obtained electrochemically in good yield in an undivided cell with a sacrificial anode.

Electrochemical synthesis of symmetrical ketones from acid chlorides

Abstract The electrochemical reduction of aroyl or arylacetyl chlorides was performed in an undivided cell fitted with a stainless steel anode and a nickel foam cathode. The electrolyses were carried out at constant current in acetonitrile as solvent, leading to the corresponding symmetrical ketones.