Extension de la réaction phosphine imide en série cyclodextrine (Synthèses et propriétés de nouvelles cyclodextrines complexantes)

Dans le développement de nouvelles synthèses, le remplacement des composés volatils organiques tels que les réactifs industriels dangereux apparaît comme important. C est aujourd'hui le défi de la chimie verte. La réaction Phosphine imide rend facile d accès certaines fonctions quadrivalentes tel que isocyanate, carbodiimide, thio-urée ou urée notamment dans des CDs. Nous avons pu démontré la sûreté, l'efficacité et la polyvalence de cette réaction avec PPH3 libre ou supporté sur polymère avec CS2, CO2 et le CO2 supercritique. Dans la deuxième partie, les propriétés physico-chimique de coordination sélective de cations métalliques et certaines propriétés de fluorescence des complexes de terre rare d'ureido-CDs ont été étudiées. Ces nouveaux systèmes se sont avérés être très sélectifs et originaux , notamment dans la coordination avec la série de lanthanide. Pour la dernière partie, la synthèse d un récepteur C2 symétrique comprenant deux CDs reliés par des liens urée à une plate-forme chirale diaza-éther-couronne est rapportée. Ce système moléculaire s'est avéré un outil efficace de complexation du Busulfan, un agent anticancéreux utilisé pour le traitement des maladie hématologiques. Enfin, un tétrapode de bis-guanidinum , premier membre d'une nouvelle famille à centres cationiques et quantité de CDs modulable est présenté. La complexation de nucléotides avec cette structure a été étudié. On observe la formation du complexe bimoléculaire combinant des inclusions dans les cavités des hydrophobes des CDs et des interactions électrostatiques entre le guanidinium et les anion phosphate.In the development of new efficient synthetic processes, the replacement of organic volatile compounds such as hazardous industrial reagents appears as a major gaol in the present day challenge for a green chemistry. It is well know that compounds containing the urea or thiourea functionality are of extended biological. As a powerful easy access to urea functionality and other main quatrivalent functions of chemistry as eg isocyanates, carbodiimide, thiourea or urea notably in CDs series, we earlier reported and demonstrated the high safety, efficiency and versatility of the phosphine imide reaction with free or polymer supported PPH3 and with CS2, CO2 or supercritical CO2. On the second part, specific physico-chemical property related to selective metal coordination and to fluorescence properties of URTF ureido-CDs rare earth complexes were investigated. This new systems were found to have very selective and original coordination processes notably with lanthanide series. For the last part, the synthesis of C2 symmetric receptor including two CDs connected by urea linkers to the chiral diazacrown ether o platform is reported. This molecular system was found to be an efficient complexion tool towards the Busulfan anticancer agent used for the treatment of haematological disorders. A novel bis-guanidinum tetrapode, the first member of a new host family with a checked number of cationic centres and CDs is presented. Its molecular recognition towards nucleodides guest was investigated. The formation of ditopic bimolecular complexe was observed combining host-guest hydrophobic inclusion into CDs and electrostatic interactions between guanidinium and phosphate anion.NANCY1-SCD Sciences & Techniques (545782101) / SudocSudocFranceF

Thermoresponsive Hydrogels in Catalysis

International audienceno abstrac

Mechanochemical synthesis of β‐cyclodextrin urea derivatives under reactive CO₂ atmosphere by tandem Staudinger aza‐Wittig ureation

National audienc

Synthèse de dérivés urées de cyclodextrines par mécanochimie sous pression de CO₂

National audienc

Cyclodextrins as Porous Material for Catalysis

International audienceno abstrac

Phosphane-Based Cyclodextrins as Mass Transfer Agents and Ligands for Aqueous Organometallic Catalysis

The replacement of hazardous solvents and the utilization of catalytic processes are two key points of the green chemistry movement, so aqueous organometallic catalytic processes are of great interest in this context. Nevertheless, these processes require not only the use of water-soluble ligands such as phosphanes to solubilise the transition metals in water, but also the use of mass transfer agents to increase the solubility of organic substrates in water. In this context, phosphanes based on a cyclodextrin skeleton are an interesting alternative since these compounds can simultaneously act as mass transfer agents and as coordinating species towards transition metals. For twenty years, various cyclodextrin-functionalized phosphanes have been described in the literature. Nevertheless, while their coordinating properties towards transition metals and their catalytic properties were fully detailed, their mass transfer agent properties were much less discussed. As these mass transfer agent properties are directly linked to the availability of the cyclodextrin cavity, the aim of this review is to demonstrate that the nature of the reaction solvent and the nature of the linker between cyclodextrin and phosphorous moieties can deeply influence the recognition properties. In addition, the impact on the catalytic activity will be also discussed

Catalytic hydrogenation of derived‐vegetable oils by Ru NPs supported onto ion‐exchange resin functionalized by β-cyclodextrin

National audienc

Cyclodextrin-grafted polymers functionalized with phosphanes: a new tool for aqueous organometallic catalysis

New cyclodextrin (CD)-grafted polymers functionalized with water-soluble phosphanes were synthesized in three steps starting from polyNAS. Once characterized by NMR spectroscopy and size-exclusion chromatography, they were used as additives in Rh-catalyzed hydroformylation of 1-hexadecene. The combined supramolecular and coordinating properties of these polymers allowed increasing the catalytic activity of the reaction without affecting the selectivities

Cyclodextrins as first and second sphere ligands for Rh(I) complexes of lower-rim PTA derivatives for use as catalysts in aqueous phase hydrogenation

International audienceno abstrac

Catalysis in Cyclodextrin-Based Unconventional Reaction Media: Recent Developments and Future Opportunities

International audienceno abstrac