Sylvie Thiebaut

Réaction d'alcoolates sur les 2-perfluoroalkyl-éthanoate d'alkyle

Abstract The reaction of alcoholates with esters of perfluoroalkylethanoic acid ( I ) and 3-perfluoroalkyl-3-fluoro-propenoic acid ( II ) has been studied. Formation of ethers of the enol ester III or the acetal IV depends on the stoichiometric conditions used. The formation of the products proceeds via a Michael-type addition and elimination of fluoride ions from the enolate formed as an intermediate.

Synthesis of perfluoroalkylatedβ-alanine and some peptide derivatives: An access to original surfactants

SummaryThe reaction of amines or sodium azide with 3-perfluoroalkyl-3-fluoroprop-2-enoate, followed by hydrogenation, affords perfluoroalkylatedβ-alanine analogues in very good yields. These compounds can be linked via an amide bond to produce peptide analogues such as carnosine or carcinine derivatives, which could have surfactive and complexing properties.

Réactivité des acides 2-perfluoroalkyléthanoı̈ques: préparation de tensioactifs originaux et application à la formulation d'émulsions–gels

Abstract 2H, 2H-perfluoroalkylethanoic acids give, under mild conditions, in the presence of alcoholic potassium hydroxide, corresponding enol ethers or ketals in very good yield. The reduction of the acid function of these derivatives and the aminolysis of the corresponding esters lead to relatively hydrophobic surfactants. These compounds have been tested to determine if they give stable gel–emulsions from fluorocarbons.

Etude de la réaction des amines sur les dérivés d'acides 2-perfluoroalkylethanoïques

Abstract 2H,2H-Perfluoroalkylethanoic acids and their derivatives compounds are potentially useful intermediates. The reaction of these with primary or secondary amines gives easy access to several perfluoroalkylated products such as imines, enamines, enaminoesters and enaminoamides in good yield and high stereoselectivity.

Etude du réarrangement de Beckmann des sels d'OTDP des oximes de cétones aromatiques et applications en synthèse

Abstract bdBeckmann rearrangement of OTDP salts of oximes of aromatic ketones and synthetic applications . Reaction between tris(dimethylamino)-phosphine, carbon tetrachloride and oximes of ketones leads to the corresponding Oximoxy-Tris-(Dimethylamino)-Phosphonium salts (OTDP salts), which are isolated in the form of hexafluorophosphates. These salts are solid and stable except if they are completely dehydrated. Their solutions, in non polar solvents like CHCl 3 , give Beckmann rearrangement at room temperature. The kinetics and mechanism have been studied by NMR. We have defined the conditions of trapping of the cationic intermediates formed in the rearrangement, leading to an effective synthesis of amidines and an access to a glycoside structure using the hemiacetalic hydroxyl group of sugar as nucleophile.

An Improved Synthesis of [btilde]-Perfluoroalkylated Analogues of [btilde]-Alanine

Abstract A very simple route to perfluoroalkylated analogues of [btilde]-alanine is proposed via a reaction between amines or sodium azide and 3-perfluoroalkyl-3-fluoro-prop-2-enoate followed by hydrogenation.

Serendipity in perfluorinated series: unexpected synthesis of 7-(perfluoroalkyl)-2,3-dihydro-5H-1,4-dioxepin-5-one

Treatment of [2-(perfluoroalkyl)-1,3-dioxolan-2-yl]acetic acids with thionyl chloride and a 48% HBr solution yields 7-polyfluoroalkyl-2,3-dihydro-5H-1,4-dioxepine-5-one. The production of this unexpected entity is explained by a rearrangement mechanism proposed in this work.