Christine Gérardin

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.

Amphiphilic and cation-complexing compounds based on peptidoamines

The synthesis of different types of amphiphilic compounds containing peptidoamine groups leads to surfactants with original properties such as the ability to coordinate metal ions. Water soluble acylcarcinine and alkylamidocarnosine surfactants are compared and the preparation of a silyloxyalkylamidocarnosine is described. The latter can be copolymerised with tetraalkoxysilanes to yield amphipathic organo-mineral solids that are also good ligands for metal cations.

Interactions of colloidal grafted silica with transition-metal cations

Synthetic silica-bearing organic groups derived from amino acids at their surface have been prepared via the sol—gel technique. The particle size of the colloidal silica obtained in this way has been assessed by different methods. The complexation of divalent metal cations, such as Cu2+, Cd2+, and Pb2+, has been studied in aqueous media by using ion-selective electrodes.

Hydrophobic tartaric acid monoamides as complexing and tensioactive agents

A simple method for the preparation of monoamide derivatives of tartaric acid is proposed. The direct synthesis of the products HOOC–CHOH–CHOH–CONHR, where R is an alkyl chain with 3, 8, 10 or 14 carbons, from tartaric acid and the corresponding amines is described. The tensioactive properties of the C8 molecule have been evaluated; this compound forms micelles in water and the critical micellar concentration has been measured. The complexing ability of these molecules toward the trivalent lanthanide cation Pr(III) has been checked with the C3 compound. The formation of a neutral complex and the hydrophobic character of these molecules make them good candidates for liquid–liquid extraction in order to extract and separate lanthanide(III) ions.

New biosurfactants containing β-lactam and triazole rings

We report the synthesis and the properties of a new class of monobactams containing a triazole ring, that are both bio- and surface-active materials. A standard procedure for β-lactam synthesis from fatty amines, aminoacid, and 2,2-bis (hydroxymethylpropionic acid), involves an intramolecular reaction. After introduction of an azido group, the reaction with acetylenic derivatives leads to a triazole ring. The critical micelle concentrations of aqueous solutions have been determined; antibiotic and antiviral activities have been evaluated.