References of "Richel, Aurore"
     in
Bookmark and Share    
See detailMicrowave-assisted transformations of carbohydrates
Richel, Aurore ULg

Report (2010)

This reports deals with the involvment of microwaves for the conversion of renewable feedstocks, and in particlar for the tranfsormation of monosaccharides and cellulose into high added value materials.

Detailed reference viewed: 21 (3 ULg)
Full Text
See detailMicrowave-assisted transformations of carbohydrates
Richel, Aurore ULg; Wathelet, Jean-Paul ULg; Paquot, Michel ULg

in SciTopics / Research Summaries by Experts (2010)

Detailed reference viewed: 52 (11 ULg)
Full Text
Peer Reviewed
See detailMicrowave-assisted synthesis of D-glucuronic acid derivatives using cost-effective solid acid catalysts
Richel, Aurore ULg; Laurent, Pascal ULg; Wathelet, Bernard ULg et al

in Tetrahedron Letters (2010), 51

Monomode microwave-assisted coupling of D-glucuronic acid with alcohols, in the presence of various impregnated acid catalysts, was successfully performed, affording in almost quantitative yields the ... [more ▼]

Monomode microwave-assisted coupling of D-glucuronic acid with alcohols, in the presence of various impregnated acid catalysts, was successfully performed, affording in almost quantitative yields the corresponding monosubstituted b-D-glucofuranosidurono-6,3-lactones in less than 10 min at 85°C. This study evidences the synergy of microwaves and impregnated acid catalysts as a fast and clean strategy in the field of carbohydrate chemistry. [less ▲]

Detailed reference viewed: 68 (28 ULg)
Full Text
See detailChimie verte et nouvelles molécules issues du Programme d'Excellence Technose
Laurent, Pascal ULg; Richel, Aurore ULg

Scientific conference (2009, October 21)

Detailed reference viewed: 83 (23 ULg)
Full Text
See detailChemical and enzymatical modifications of sugar derived from lignocellulose
Richard, Gaetan ULg; Laurent, Pascal ULg; Nott, Katherine ULg et al

Poster (2009, January)

Actually, biorefinery is increasingly considered as a promising alternative to petroleum chemistry, since it aims at not only the replacement of fossil energy but also the development of chemicals from ... [more ▼]

Actually, biorefinery is increasingly considered as a promising alternative to petroleum chemistry, since it aims at not only the replacement of fossil energy but also the development of chemicals from biomass, with applications such as detergents, phytopharmaceutics, solvents, plastics, etc. The valorisation of carbohydrates from renewable raw materials is currently the subject of numerous researches. In this context, the synthesis of new surfactants derived from the sugars issued from the lignocellulose hydrolysis was undertaken by chemical or enzymatic routes. In this poster, the examples of glucose, cellobiose and uronic acids will be discussed. Whatever the way used, the reaction conditions (use of a catalyst, protection/deprotection steps, type of solvent, presence of co-solvent, reactant concentrations, etc) were optimized to yield a panel of carbohydrate derivatives (some examples of the structures obtained are given above). These differ by the nature of the alkyl chain (in length and in degree of saturation), the type of chemical bond (amide, ester, thioester, acetal), and the position of substitution. The impact of these differences on the techno-functional properties of these modified sugars will be evaluated. [less ▲]

Detailed reference viewed: 80 (19 ULg)
Full Text
See detailSynthèse de nouveaux surfactants dérivés des acides D-glucuronique et D-galacturonique.
Laurent, Pascal ULg; Richel, Aurore ULg; Richard, Gaetan ULg et al

Poster (2008)

A l'heure actuelle, le bioraffinage se présente de plus en plus comme une alternative prometteuse aux filières pétrochimiques puisqu'il vise à la fois le remplacement d'une partie du pétrole comme source ... [more ▼]

A l'heure actuelle, le bioraffinage se présente de plus en plus comme une alternative prometteuse aux filières pétrochimiques puisqu'il vise à la fois le remplacement d'une partie du pétrole comme source d'énergie et le développement de produits chimiques issus de la biomasse (végétale principalement) tels que détergents, produits phytopharmaceutiques, dissolvants, matières plastiques, etc. La valorisation de carbohydrates provenant de matières premières renouvelables [1] fait ainsi actuellement l'objet de nombreuses recherches. Dans ce cadre, la synthèse de nouveaux tensioactifs non ioniques dérivés des acides Dglucuronique et D-galacturonique a été effectuée de manière chimique et/ou enzymatique. [less ▲]

Detailed reference viewed: 61 (9 ULg)
See detailNatural Oils and Fats as Renewable Raw Materials for the Polymer Industry
Richel, Aurore ULg

Scientific conference (2007, March 09)

The valorisation of natural (renewable) vegetable oils and animal fats in the polymer industry is described as a example of "green chemistry". We underline that these renewable feedstocks find brilliant ... [more ▼]

The valorisation of natural (renewable) vegetable oils and animal fats in the polymer industry is described as a example of "green chemistry". We underline that these renewable feedstocks find brilliant applications as additives, polymers or co-polymers. These materials offer convenient alternatives to classical petrochemical-based compounds. [less ▲]

Detailed reference viewed: 19 (4 ULg)
See detailControl of radical reactions by transition-metal complexes
Richel, Aurore ULg

Doctoral thesis (2007)

The overall goal of this Ph.D. is to contribute to the conception, the synthesis and the characterisation of original homogeneous ruthenium-based catalytic systems (or heterobimetallic ruthenium-titanium ... [more ▼]

The overall goal of this Ph.D. is to contribute to the conception, the synthesis and the characterisation of original homogeneous ruthenium-based catalytic systems (or heterobimetallic ruthenium-titanium systems), highly active and effective towards atom transfer radical addition (ATRA) and polymerisation (ATRP) of several representative vinyl monomers. As catalytic performances may be tuned by the nature and the structure of the ligands around the metallic core, we are intending to systematically elucidate (by NMR and electrochemistry) the relations between stereoelectronic ligands parameters and the catalytic activity. Microwave irradition is also considered as an unexpected heating source for performing radical reactions. [less ▲]

Detailed reference viewed: 56 (17 ULg)
Full Text
Peer Reviewed
See detailMicrowave-enhanced ruthenium-catalysed atom transfer radical additions
Borguet, Yannick ULg; Richel, Aurore ULg; Delfosse, Sbastien et al

in Tetrahedron Letters (2007), 48(36), 6334-6338

The first monomode microwave-assisted atom transfer radical additions (ATRA) of carbon tetrachloride to various olefins were successfully performed, affording the adducts with almost quantitative yields ... [more ▼]

The first monomode microwave-assisted atom transfer radical additions (ATRA) of carbon tetrachloride to various olefins were successfully performed, affording the adducts with almost quantitative yields in less than 10 min at 160 'C. (c) 2007 Elsevier Ltd. All rights reserved. [less ▲]

Detailed reference viewed: 39 (17 ULg)
Full Text
Peer Reviewed
See detailElectrochemistry as a correlation tool with the catalytic activities in [RuCl2(p-cymene)(PAr3)]-catalysed Kharasch additions
Richel, Aurore ULg; Demonceau, Albert ULg; Noels, Alfred ULg

in Tetrahedron Letters (2006), 47

[RuCl2(p-cymene)] complexes containing triarylphosphine ligands with various substituents at the para position were used to catalyse the atom transfer radical addition of carbon tetrachloride to various ... [more ▼]

[RuCl2(p-cymene)] complexes containing triarylphosphine ligands with various substituents at the para position were used to catalyse the atom transfer radical addition of carbon tetrachloride to various olefins, and their catalytic activities were nicely correlated with their electrochemical parameters. [less ▲]

Detailed reference viewed: 18 (7 ULg)
See detailProjet FIRST Europe Objectif 1 (OLIPOL-Synthèse de (co)-polymères d'origine végétale par voie catalytique) Rapport Final
Richel, Aurore ULg

Report (2006)

Le principal objectif visé par ce programme de recherche est de mettre au point des catalyseurs efficaces, capables de polymériser par voie radicalaire contrôlée certaines oléfines internes (peu ... [more ▼]

Le principal objectif visé par ce programme de recherche est de mettre au point des catalyseurs efficaces, capables de polymériser par voie radicalaire contrôlée certaines oléfines internes (peu réactionnelles) et, éventuellement, l'huile de lin. Nous tenterons aussi d'aborder la copolymérisation de l'huile de lin avec des monomères de grande consommation (styrène et (méth)acrylates) afin de mettre au point, au départ d'une matière première d'origine végétale et renouvelable, des matériaux polymères nouveaux, non polluants et bon marché. Méthodologie Le développement de nouveaux systèmes catalytiques actifs et sélectifs (aussi bien en réaction de Kharasch qu'en ATRP) sous-tend une connaissance approfondie des relations structure-activité. De ce fait, des corrélations entre les paramètres stéréoélectroniques des ligands, entre certaines propriétés physico-chimiques des complexes organométalliques synthétisés et leur activité en ATRA et ATRP ont été obtenues grâce à diverses techniques d'analyse (voltamétrie cyclique, RMN, analyse thermogravimétrique, …). L'amélioration des performances des complexes métalliques proposés s'opère donc grâce à une modification raisonnée des ligands entourant le centre métallique, ce qui est défini par le terme d'"ingénierie catalytique". Après avoir amélioré les performances catalytiques de certains systèmes déjà existants et aborder certains aspects mécanistiques, nous nous intéresserons donc à la possibilité éventuelle de polymériser certaines oléfines internes. Résultats obtenus et publications 1. Variations autour de Ru-Cp# : étude des complexes de type [RuX(Cp#)(PR3)2] 2. Complexes [RuCl2(p-cymène)PR3] Résultats ATRP et Kharasch Etude électrochimique et RMN (1H et 31P) du comportement des différents complexes dans les conditions de polymérisation 3. Réaction de Kharasch catalysée par les complexes de type [RuCl2(p-cymène)PAr3] Corrélation entre les paramètres électroniques de ces complexes et leur activité catalytique Réaction de Kharasch assistée par micro-ondes 4. Complexes hétérobimétalliques à base de ruthénium et de titane 5. Complexes de type métal-carbène 5.1. Complexes préformés 5.2. Complexes générés in situ 6. Complexes de type métal-carborane 7. Test de polymérisation de l'huile de lin [less ▲]

Detailed reference viewed: 26 (6 ULg)
See detailControlled radical polymerization of vinyl monomers catalyzed by ruthenium N-heterocyclic carbene complexes
Delfosse, Sébastien; Richel, Aurore ULg; Delaude, Lionel ULg et al

in Matyjaszewski, K. (Ed.) Progress in Controlled/Living Radical Polymerization / ACS Symposium Series 944 (2006)

The relative catalytic activities of a series of ruthenium-based complexes of the general formula [RuCl2(p-cymene)(NHC)], [RuCl2(=CHPh)(PR3)(NHC)] and [RuCl2(=CHPh)(NHC)2] (NHC is a N-heterocyclic carbene ... [more ▼]

The relative catalytic activities of a series of ruthenium-based complexes of the general formula [RuCl2(p-cymene)(NHC)], [RuCl2(=CHPh)(PR3)(NHC)] and [RuCl2(=CHPh)(NHC)2] (NHC is a N-heterocyclic carbene ligand) were determined by investigating the atom transfer radical polymerization (ATRP) of methyl mathacrylate and styrene. The catalytic activity of a variety of related [RuCl(O^N)(=CHR)(NHC)] complexes and their cationic couterparts, [Ru(O^N)(=CHR)(NHC)]+BF4- (R = Ph or OEt, O^N is a Schiff base ligand), is also reported. The results clearly demonstrate that, with both methyl methacrylate and styrene, subtle modifications of the substituents of the NHC ligand lead to dramatic changes in the ability of the resulting ruthenium complexes to favor the occurence of a well-behaved ATRP. [less ▲]

Detailed reference viewed: 17 (3 ULg)
See detailMétathèse des oléfines et réactions radicalaires catalysées par des complexes ruthénium-carbène N-hétérocycliques
Demonceau, Albert ULg; Delfosse, Sébastien; Richel, Aurore ULg et al

Scientific conference (2005, November)

Detailed reference viewed: 38 (3 ULg)
See detailMicrowave-assisted ruthenium-catalysed atom transfer radical reactions
Delfosse, Sébastien; Richel, Aurore ULg; Wei, H. et al

Poster (2005, August)

Detailed reference viewed: 14 (0 ULg)
Full Text
See detailUtilisation des techniques électrochimiques pour l'étude des mécanismes de polymérisation
Richel, Aurore ULg

Scientific conference (2005)

L'utilisation des méthodes éléctrchimiques dans le domaine de la polymérisation esr abordée comme moyen d'étude des mécanismes de polymérisation. Les polymérisations "électro-amorcées" sont également ... [more ▼]

L'utilisation des méthodes éléctrchimiques dans le domaine de la polymérisation esr abordée comme moyen d'étude des mécanismes de polymérisation. Les polymérisations "électro-amorcées" sont également discutées. [less ▲]

Detailed reference viewed: 24 (3 ULg)
Full Text
See detailMicrowave-Enhanced Ruthenium Catalysed Atom Transfer Radical Additions
Richel, Aurore ULg; Leclerc, Alain; Demonceau, Albert ULg et al

Poster (2005)

Detailed reference viewed: 16 (6 ULg)