Stéphanie Legoupy

Ionic liquid supported tin reagents for Stille cross coupling reactions

New ionic liquid supported tin reagents were synthesized for use in Stille cross coupling reactions at low reaction temperatures and with the possibility for recycling the tin compounds.

Solvent-free direct reductive amination by catalytic use of an organotin reagent incorporated on an ionic liquid.

An organotin reagent supported on an ionic liquid was used as a highly effective catalyst (down to 0.1 mol%) for the direct reductive amination of aldehydes and ketones using PhSiH3; this solvent-free method facilitates purification of the products, thus minimizing the contamination by tin.

Rapid access to acyclic nucleosides via conjugate addition

The synthesis of several acyclic nucleosides 5 and 6, analogs of penciclovir, was achieved by Michael addition as the key step. This reaction worked not only for the protected natural bases but even for the less nucleophilic deaza purine and deaza pyrimidine.

Regio- and stereoselective allylic fluorination using chiral rhenium complexes

Abstract The first example of metal mediated regio- and stereoselective allylic fluorination using chiral rhenium complexes is reported.

Synthesis and reactivity of new chiral rhenium complexes of unsaturated alcohols

Abstract New rhenium complexes of allylic, homoallylic and propargylic alcohols have been prepared. Starting from the allyl alcohol complex, a multistep sequence involving a chemoselective oxidation, a Wittig reaction and a reduction leads to a conjugated dienone and dienol selectively complexed at only one double bond.

A New Synthetic Route to β-Unsubstituted β-Lactones by Intramolecular Cyclization

Abstract When carboxylic acids β-substituted by a tert-butoxy group were treated with thionyl chloride, an intermediate acyl chloride β-substituted by a hydroxyl group was likely formed. Its subsequent intramolecular cyclization produced novel β-lactones in one step. Two enantiomerically enriched lactones could be prepared via intermediates obtained by enzymatic hydrolysis.

New chiral rhenium complexes of unsaturated alcohols: preparation and reactivity

Abstract New chiral rhenium complexes of allylic, homoallylic and propargylic alcohols have been prepared and their reactivity versus various reagents has been studied. Starting from the allyl alcohol complex, a multistep sequence involving a chemoselective oxidation, a Wittig reaction and a reduction led without bond-shift to conjugated dienone and dienol. The complexed allyl acetate, prepared by reaction of acetic anhydride on the complexed allyl alcohol reacted with sodium dimethylmalonate in a diastereoselective fashion.

Syntheses via a direct arylation method of push–pull molecules based on triphenylamine and 3-cyano-4-hexyloxythiophene moieties

Synthetic access to new push-pull molecules based on 3-cyano-4-hexyloxythiophene and triphenylamine moieties is presented herein using a clean methodology. The key step involves a direct heteroarylation coupling reaction in the presence of a homogeneous or heterogeneous [Pd] catalyst followed by Knoevenagel condensation performed in ethanol as a solvent. Structure-electronic property relationships of the new molecular materials are discussed and then their use as donors in bilayer planar heterojunction solar cells is investigated.

Ionic liquid supported organotin reagents to prepare molecular imaging and therapy agents

Efficiency of ionic liquid supported organotin reagents in halodemetalation reaction has been investigated. High radiochemical yields of astatinated and iodinated compounds have been obtained using simple work-up procedure. This methodology represents a straightforward approach for the preparation of molecular imaging and therapy agents in nuclear medicine.

Synthesis of novel derivatives of murrayafoline A and their inhibitory effect on LPS-stimulated production of pro-inflammatory cytokines in bone marrow-derived dendritic cells

A series of N-substituted-1,2,3-triazole murrayafoline A derivatives were successfully synthesized using click azide–alkyne Huisgen cycloaddition reaction between 1-methoxy-3-methyl-9-(3-azido)-propyl-9H-carbazole and substituted alkynes. Their chemical structures were confirmed by 1H, 13C NMR and HR-ESI–MS spectral data. In addition, the interested effects on LPS-stimulated production of pro-inflammatory cytokines in bone marrow-derived dendritic cells of synthetic murrayafoline A derivatives were also investigated. Our results indicated that murrayafoline A derivatives containing 1,2,3-triazole nucleus potentially possessed anti-inflammatory action through inhibiting production of IL-6, IL-12 p40 and TNF-α.