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Daniel Taton - One of the best experts on this subject based on the ideXlab platform.
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intramolecular quaternization as folding strategy for the synthesis of catalytically active imidazolium based single chain nanoparticles
ACS Macro Letters, 2017Co-Authors: Daniel Taton, Romain Lambert, Annelaure WirotiusAbstract:A novel synthetic strategy to single chain nanoparticles (SCNP) based on a previously unexplored intramolecular reaction as a means to autonomously fold a parent copolymer precursor is reported. The latter is a statistical styrenic-type copolymer synthesized by RAFT polymerization and is composed of four different comonomer units, including styrene, grafted poly(ethylene oxide) chains, and antagonist benzimidazol- and chlorobenzyl-based units. The two latter functions are reacted together by a quaternization reaction to spark the folding process, creating imidazolium-based cross-link points. Formation of SCNP with a hydrodynamic diameter <10 nm is established by a combination of different characterization techniques. A subsequent metathesis step for exchanging chloride anions by acetate ones of imidazolium moieties enables a use of SCNP for the organocatalyzed Benzoin Condensation, thanks to the ability of imidazolium acetate to generate SCNP-supported N-heterocyclic carbenes as organocatalysts.
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post polymerization modification and organocatalysis using reactive statistical poly ionic liquid based copolymers
Polymer, 2014Co-Authors: Paul Coupillaud, Joan Vignolle, Daniel Taton, David MecerreyesAbstract:Abstract Copoly(ionic liquid)s (coPILs) based on poly(styrene)- co -poly(4-vinylbenzylbutylimidazolium) with different anions (Cl − and HCO 3 − ), denoted as PS- co -PVBnBuImCl 1 and PS- co -PVBnBuImHCO 3 2 , were used as reactive polymers for the purpose of post-polymerization modification and organic catalysis. While coPIL 1 could be derived into the corresponding poly( N -heterocyclic carbene)-silver transition metal complex referred to as poly(NHC–Ag) by a simple deprotonation/metallation sequence utilizing Ag 2 O, coPIL 2 was found to quantitatively react with various electrophiles, including CS 2 , isothiocyanate and transition metals (based on Pd and Au) upon formal loss of “H 2 CO 3 , affording the post-functionalized poly(NHC-CS 2 ), poly(NHC-isothiocyanate) and poly(NHC-Met) (Met = Au, Pd) copolymers. The catalytic activity of both coPILs 1 and 2 was also examined in cyclic carbonate formation by reaction between CO 2 and propylene oxide and in the Benzoin Condensation, respectively.
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functional mesoporous poly ionic liquid based copolymer monoliths from synthesis to catalysis and microporous carbon production
Polymer, 2014Co-Authors: Danuta Kuzmicz, Paul Coupillaud, Giordano Vendraminetto, Martina Ambrogi, Joan Vignolle, Yongjun Men, Daniel TatonAbstract:Abstract Ionic liquid-functionalized mesoporous polymeric networks with specific surface area up to 935 m 2 /g have been successfully synthesized one pot by solvothermal copolymerization of divinylbenzene and monomeric ionic liquids. The as-obtained polymers exhibit a monolithic structure featuring large pore volumes, an abundant mesoporosity and an adjustable content of ionic liquids. The effect of the reaction conditions on the pore structure has been studied in detail. These poly(ionic liquid)-based porous networks (PILPNs) have then been employed as precursors in two distinct applications, namely organocatalysis and production of microporous carbon monoliths. Selected organocatalyzed reactions, including carbonatation of propylene oxide by cycloaddition with carbon dioxide, Benzoin Condensation, and cyanosilylation of benzaldehyde have been readily triggered by PILPNs acting as crosslinked polymer-supported (pre)catalysts. The two latter reactions required the prior deprotonation of the imidazolium salt units with a strong base to successfully generate polymer-supported N -heterocyclic carbenes, referred to as poly(NHC)s. Facile recycling and reuse of polymer-supported (pre)catalysts was achieved by simple filtration owing to the heterogeneous reaction conditions. Furthermore, PILPNs could be easily converted into microporous carbon monoliths via CO 2 activation.
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Functional mesoporous poly(ionic liquid)-based copolymer monoliths: From synthesis to catalysis and microporous carbon production
Polymer (United Kingdom), 2014Co-Authors: Danuta Kuzmicz, Paul Coupillaud, Giordano Vendraminetto, Martina Ambrogi, Joan Vignolle, Daniel Taton, Yongjun Men, Jiayin YuanAbstract:Ionic liquid-functionalized mesoporous polymeric networks with specific surface area up to 935 m2/g have been successfully synthesized one pot by solvothermal copolymerization of divinylbenzene and monomeric ionic liquids. The as-obtained polymers exhibit a monolithic structure featuring large pore volumes, an abundant mesoporosity and an adjustable content of ionic liquids. The effect of the reaction conditions on the pore structure has been studied in detail. These poly(ionic liquid)-based porous networks (PILPNs) have then been employed as precursors in two distinct applications, namely organocatalysis and production of microporous carbon monoliths. Selected organocatalyzed reactions, including carbonatation of propylene oxide by cycloaddition with carbon dioxide, Benzoin Condensation, and cyanosilylation of benzaldehyde have been readily triggered by PILPNs acting as crosslinked polymer-supported (pre)catalysts. The two latter reactions required the prior deprotonation of the imidazolium salt units with a strong base to successfully generate polymer-supported N-heterocyclic carbenes, referred to as poly(NHC)s. Facile recycling and reuse of polymer-supported (pre)catalysts was achieved by simple filtration owing to the heterogeneous reaction conditions. Furthermore, PILPNs could be easily converted into microporous carbon monoliths via CO2activation. © 2014 Elsevier Ltd. All rights reserved.
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Poly(ionic liquid)s Based on Imidazolium Hydrogen Carbonate Monomer Units as Recyclable Polymer-Supported N-Heterocyclic Carbenes: Use in Organocatalysis
Journal of Polymer Science Part A: Polymer Chemistry, 2013Co-Authors: Paul Coupillaud, Joan Vignolle, Julien Pinaud, Nicolas Guidolin, Mareva Fevre, David Mecerreyes, Ellen Veaudecrenne, Daniel TatonAbstract:Synthesis of novel poly(ionic liquid)s, namely, poly(1-vinyl-3-alkylimidazolium hydrogen carbonate)s, denoted as poly([NHC(H)][HCO3])s or PVRImHCO(3), where R is an alkyl group (R=ethyl, butyl, phenylethyl, dodecyl), is described. Two distinct synthetic routes were explored. The first method is based on the free-radical polymerization (FRP) of 1-vinyl-3-alkylimidazolium monomers featuring a hydrogen carbonate counter anion (HCO3-), denoted as VRImHCO(3). The latter monomers were readily synthesized by alkylation of 1-vinylimidazole (VIm), followed by direct anion exchange of 1-vinyl-3-alkylimidazolium bromide monomers (VRImBr), using potassium hydrogen carbonate (KHCO3) in methanol at room temperature. Alternatively, the same anion exchange method could be applied onto FRP-derived poly(1-vinyl-3-alkylimidazolium bromide) precursors (PVRImBr). All PVRImHCO(3) salts proved air stable and could be manipulated without any particular precautions. They could serve as polymer-supported precatalysts to generate polymer-supported N-heterocyclic carbenes, referred to as poly(NHC)s, formally by a loss of H2CO3 (H2O +CO2) in solution. This was demonstrated through selected organocatalyzed reactions of molecular chemistry, known as being efficiently mediated by molecular NHC catalysts, including Benzoin Condensation, transesterification and cyanosilylation of aldehyde. Of particular interest, recycling of the polymer-supported precatalysts was possible by re-carboxylation of in situ generated poly(NHC)s. Organocatalyzed reactions could be performed with excellent yields, even after five catalytic cycles.
Paul Coupillaud - One of the best experts on this subject based on the ideXlab platform.
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post polymerization modification and organocatalysis using reactive statistical poly ionic liquid based copolymers
Polymer, 2014Co-Authors: Paul Coupillaud, Joan Vignolle, Daniel Taton, David MecerreyesAbstract:Abstract Copoly(ionic liquid)s (coPILs) based on poly(styrene)- co -poly(4-vinylbenzylbutylimidazolium) with different anions (Cl − and HCO 3 − ), denoted as PS- co -PVBnBuImCl 1 and PS- co -PVBnBuImHCO 3 2 , were used as reactive polymers for the purpose of post-polymerization modification and organic catalysis. While coPIL 1 could be derived into the corresponding poly( N -heterocyclic carbene)-silver transition metal complex referred to as poly(NHC–Ag) by a simple deprotonation/metallation sequence utilizing Ag 2 O, coPIL 2 was found to quantitatively react with various electrophiles, including CS 2 , isothiocyanate and transition metals (based on Pd and Au) upon formal loss of “H 2 CO 3 , affording the post-functionalized poly(NHC-CS 2 ), poly(NHC-isothiocyanate) and poly(NHC-Met) (Met = Au, Pd) copolymers. The catalytic activity of both coPILs 1 and 2 was also examined in cyclic carbonate formation by reaction between CO 2 and propylene oxide and in the Benzoin Condensation, respectively.
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functional mesoporous poly ionic liquid based copolymer monoliths from synthesis to catalysis and microporous carbon production
Polymer, 2014Co-Authors: Danuta Kuzmicz, Paul Coupillaud, Giordano Vendraminetto, Martina Ambrogi, Joan Vignolle, Yongjun Men, Daniel TatonAbstract:Abstract Ionic liquid-functionalized mesoporous polymeric networks with specific surface area up to 935 m 2 /g have been successfully synthesized one pot by solvothermal copolymerization of divinylbenzene and monomeric ionic liquids. The as-obtained polymers exhibit a monolithic structure featuring large pore volumes, an abundant mesoporosity and an adjustable content of ionic liquids. The effect of the reaction conditions on the pore structure has been studied in detail. These poly(ionic liquid)-based porous networks (PILPNs) have then been employed as precursors in two distinct applications, namely organocatalysis and production of microporous carbon monoliths. Selected organocatalyzed reactions, including carbonatation of propylene oxide by cycloaddition with carbon dioxide, Benzoin Condensation, and cyanosilylation of benzaldehyde have been readily triggered by PILPNs acting as crosslinked polymer-supported (pre)catalysts. The two latter reactions required the prior deprotonation of the imidazolium salt units with a strong base to successfully generate polymer-supported N -heterocyclic carbenes, referred to as poly(NHC)s. Facile recycling and reuse of polymer-supported (pre)catalysts was achieved by simple filtration owing to the heterogeneous reaction conditions. Furthermore, PILPNs could be easily converted into microporous carbon monoliths via CO 2 activation.
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Functional mesoporous poly(ionic liquid)-based copolymer monoliths: From synthesis to catalysis and microporous carbon production
Polymer (United Kingdom), 2014Co-Authors: Danuta Kuzmicz, Paul Coupillaud, Giordano Vendraminetto, Martina Ambrogi, Joan Vignolle, Daniel Taton, Yongjun Men, Jiayin YuanAbstract:Ionic liquid-functionalized mesoporous polymeric networks with specific surface area up to 935 m2/g have been successfully synthesized one pot by solvothermal copolymerization of divinylbenzene and monomeric ionic liquids. The as-obtained polymers exhibit a monolithic structure featuring large pore volumes, an abundant mesoporosity and an adjustable content of ionic liquids. The effect of the reaction conditions on the pore structure has been studied in detail. These poly(ionic liquid)-based porous networks (PILPNs) have then been employed as precursors in two distinct applications, namely organocatalysis and production of microporous carbon monoliths. Selected organocatalyzed reactions, including carbonatation of propylene oxide by cycloaddition with carbon dioxide, Benzoin Condensation, and cyanosilylation of benzaldehyde have been readily triggered by PILPNs acting as crosslinked polymer-supported (pre)catalysts. The two latter reactions required the prior deprotonation of the imidazolium salt units with a strong base to successfully generate polymer-supported N-heterocyclic carbenes, referred to as poly(NHC)s. Facile recycling and reuse of polymer-supported (pre)catalysts was achieved by simple filtration owing to the heterogeneous reaction conditions. Furthermore, PILPNs could be easily converted into microporous carbon monoliths via CO2activation. © 2014 Elsevier Ltd. All rights reserved.
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poly ionic liquid s based on imidazolium hydrogen carbonate monomer units as recyclable polymer supported n heterocyclic carbenes use in organocatalysis
Journal of Polymer Science Part A, 2013Co-Authors: Paul Coupillaud, Joan Vignolle, Julien Pinaud, Nicolas Guidolin, Mareva FevreAbstract:Synthesis of novel poly(ionic liquid)s, namely, poly(1-vinyl-3-alkylimidazolium hydrogen carbonate)s, denoted as poly([NHC(H)][HCO3])s or PVRImHCO3, where R is an alkyl group (R = ethyl, butyl, phenylethyl, dodecyl), is described. Two distinct synthetic routes were explored. The first method is based on the free-radical polymerization (FRP) of 1-vinyl-3-alkylimidazolium monomers featuring a hydrogen carbonate counter anion (HCO3−), denoted as VRImHCO3. The latter monomers were readily synthesized by alkylation of 1-vinylimidazole (VIm), followed by direct anion exchange of 1-vinyl-3-alkylimidazolium bromide monomers (VRImBr), using potassium hydrogen carbonate (KHCO3) in methanol at room temperature. Alternatively, the same anion exchange method could be applied onto FRP-derived poly(1-vinyl-3-alkylimidazolium bromide) precursors (PVRImBr). All PVRImHCO3 salts proved air stable and could be manipulated without any particular precautions. They could serve as polymer-supported precatalysts to generate polymer-supported N-heterocyclic carbenes, referred to as poly(NHC)s, formally by a loss of “H2CO3” (H2O +CO2) in solution. This was demonstrated through selected organocatalyzed reactions of molecular chemistry, known as being efficiently mediated by molecular NHC catalysts, including Benzoin Condensation, transesterification and cyanosilylation of aldehyde. Of particular interest, recycling of the polymer-supported precatalysts was possible by re-carboxylation of in situ generated poly(NHC)s. Organocatalyzed reactions could be performed with excellent yields, even after five catalytic cycles. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4530–4540
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Poly(ionic liquid)s Based on Imidazolium Hydrogen Carbonate Monomer Units as Recyclable Polymer-Supported N-Heterocyclic Carbenes: Use in Organocatalysis
Journal of Polymer Science Part A: Polymer Chemistry, 2013Co-Authors: Paul Coupillaud, Joan Vignolle, Julien Pinaud, Nicolas Guidolin, Mareva Fevre, David Mecerreyes, Ellen Veaudecrenne, Daniel TatonAbstract:Synthesis of novel poly(ionic liquid)s, namely, poly(1-vinyl-3-alkylimidazolium hydrogen carbonate)s, denoted as poly([NHC(H)][HCO3])s or PVRImHCO(3), where R is an alkyl group (R=ethyl, butyl, phenylethyl, dodecyl), is described. Two distinct synthetic routes were explored. The first method is based on the free-radical polymerization (FRP) of 1-vinyl-3-alkylimidazolium monomers featuring a hydrogen carbonate counter anion (HCO3-), denoted as VRImHCO(3). The latter monomers were readily synthesized by alkylation of 1-vinylimidazole (VIm), followed by direct anion exchange of 1-vinyl-3-alkylimidazolium bromide monomers (VRImBr), using potassium hydrogen carbonate (KHCO3) in methanol at room temperature. Alternatively, the same anion exchange method could be applied onto FRP-derived poly(1-vinyl-3-alkylimidazolium bromide) precursors (PVRImBr). All PVRImHCO(3) salts proved air stable and could be manipulated without any particular precautions. They could serve as polymer-supported precatalysts to generate polymer-supported N-heterocyclic carbenes, referred to as poly(NHC)s, formally by a loss of H2CO3 (H2O +CO2) in solution. This was demonstrated through selected organocatalyzed reactions of molecular chemistry, known as being efficiently mediated by molecular NHC catalysts, including Benzoin Condensation, transesterification and cyanosilylation of aldehyde. Of particular interest, recycling of the polymer-supported precatalysts was possible by re-carboxylation of in situ generated poly(NHC)s. Organocatalyzed reactions could be performed with excellent yields, even after five catalytic cycles.
Joan Vignolle - One of the best experts on this subject based on the ideXlab platform.
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post polymerization modification and organocatalysis using reactive statistical poly ionic liquid based copolymers
Polymer, 2014Co-Authors: Paul Coupillaud, Joan Vignolle, Daniel Taton, David MecerreyesAbstract:Abstract Copoly(ionic liquid)s (coPILs) based on poly(styrene)- co -poly(4-vinylbenzylbutylimidazolium) with different anions (Cl − and HCO 3 − ), denoted as PS- co -PVBnBuImCl 1 and PS- co -PVBnBuImHCO 3 2 , were used as reactive polymers for the purpose of post-polymerization modification and organic catalysis. While coPIL 1 could be derived into the corresponding poly( N -heterocyclic carbene)-silver transition metal complex referred to as poly(NHC–Ag) by a simple deprotonation/metallation sequence utilizing Ag 2 O, coPIL 2 was found to quantitatively react with various electrophiles, including CS 2 , isothiocyanate and transition metals (based on Pd and Au) upon formal loss of “H 2 CO 3 , affording the post-functionalized poly(NHC-CS 2 ), poly(NHC-isothiocyanate) and poly(NHC-Met) (Met = Au, Pd) copolymers. The catalytic activity of both coPILs 1 and 2 was also examined in cyclic carbonate formation by reaction between CO 2 and propylene oxide and in the Benzoin Condensation, respectively.
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functional mesoporous poly ionic liquid based copolymer monoliths from synthesis to catalysis and microporous carbon production
Polymer, 2014Co-Authors: Danuta Kuzmicz, Paul Coupillaud, Giordano Vendraminetto, Martina Ambrogi, Joan Vignolle, Yongjun Men, Daniel TatonAbstract:Abstract Ionic liquid-functionalized mesoporous polymeric networks with specific surface area up to 935 m 2 /g have been successfully synthesized one pot by solvothermal copolymerization of divinylbenzene and monomeric ionic liquids. The as-obtained polymers exhibit a monolithic structure featuring large pore volumes, an abundant mesoporosity and an adjustable content of ionic liquids. The effect of the reaction conditions on the pore structure has been studied in detail. These poly(ionic liquid)-based porous networks (PILPNs) have then been employed as precursors in two distinct applications, namely organocatalysis and production of microporous carbon monoliths. Selected organocatalyzed reactions, including carbonatation of propylene oxide by cycloaddition with carbon dioxide, Benzoin Condensation, and cyanosilylation of benzaldehyde have been readily triggered by PILPNs acting as crosslinked polymer-supported (pre)catalysts. The two latter reactions required the prior deprotonation of the imidazolium salt units with a strong base to successfully generate polymer-supported N -heterocyclic carbenes, referred to as poly(NHC)s. Facile recycling and reuse of polymer-supported (pre)catalysts was achieved by simple filtration owing to the heterogeneous reaction conditions. Furthermore, PILPNs could be easily converted into microporous carbon monoliths via CO 2 activation.
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Functional mesoporous poly(ionic liquid)-based copolymer monoliths: From synthesis to catalysis and microporous carbon production
Polymer (United Kingdom), 2014Co-Authors: Danuta Kuzmicz, Paul Coupillaud, Giordano Vendraminetto, Martina Ambrogi, Joan Vignolle, Daniel Taton, Yongjun Men, Jiayin YuanAbstract:Ionic liquid-functionalized mesoporous polymeric networks with specific surface area up to 935 m2/g have been successfully synthesized one pot by solvothermal copolymerization of divinylbenzene and monomeric ionic liquids. The as-obtained polymers exhibit a monolithic structure featuring large pore volumes, an abundant mesoporosity and an adjustable content of ionic liquids. The effect of the reaction conditions on the pore structure has been studied in detail. These poly(ionic liquid)-based porous networks (PILPNs) have then been employed as precursors in two distinct applications, namely organocatalysis and production of microporous carbon monoliths. Selected organocatalyzed reactions, including carbonatation of propylene oxide by cycloaddition with carbon dioxide, Benzoin Condensation, and cyanosilylation of benzaldehyde have been readily triggered by PILPNs acting as crosslinked polymer-supported (pre)catalysts. The two latter reactions required the prior deprotonation of the imidazolium salt units with a strong base to successfully generate polymer-supported N-heterocyclic carbenes, referred to as poly(NHC)s. Facile recycling and reuse of polymer-supported (pre)catalysts was achieved by simple filtration owing to the heterogeneous reaction conditions. Furthermore, PILPNs could be easily converted into microporous carbon monoliths via CO2activation. © 2014 Elsevier Ltd. All rights reserved.
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poly ionic liquid s based on imidazolium hydrogen carbonate monomer units as recyclable polymer supported n heterocyclic carbenes use in organocatalysis
Journal of Polymer Science Part A, 2013Co-Authors: Paul Coupillaud, Joan Vignolle, Julien Pinaud, Nicolas Guidolin, Mareva FevreAbstract:Synthesis of novel poly(ionic liquid)s, namely, poly(1-vinyl-3-alkylimidazolium hydrogen carbonate)s, denoted as poly([NHC(H)][HCO3])s or PVRImHCO3, where R is an alkyl group (R = ethyl, butyl, phenylethyl, dodecyl), is described. Two distinct synthetic routes were explored. The first method is based on the free-radical polymerization (FRP) of 1-vinyl-3-alkylimidazolium monomers featuring a hydrogen carbonate counter anion (HCO3−), denoted as VRImHCO3. The latter monomers were readily synthesized by alkylation of 1-vinylimidazole (VIm), followed by direct anion exchange of 1-vinyl-3-alkylimidazolium bromide monomers (VRImBr), using potassium hydrogen carbonate (KHCO3) in methanol at room temperature. Alternatively, the same anion exchange method could be applied onto FRP-derived poly(1-vinyl-3-alkylimidazolium bromide) precursors (PVRImBr). All PVRImHCO3 salts proved air stable and could be manipulated without any particular precautions. They could serve as polymer-supported precatalysts to generate polymer-supported N-heterocyclic carbenes, referred to as poly(NHC)s, formally by a loss of “H2CO3” (H2O +CO2) in solution. This was demonstrated through selected organocatalyzed reactions of molecular chemistry, known as being efficiently mediated by molecular NHC catalysts, including Benzoin Condensation, transesterification and cyanosilylation of aldehyde. Of particular interest, recycling of the polymer-supported precatalysts was possible by re-carboxylation of in situ generated poly(NHC)s. Organocatalyzed reactions could be performed with excellent yields, even after five catalytic cycles. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4530–4540
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Poly(ionic liquid)s Based on Imidazolium Hydrogen Carbonate Monomer Units as Recyclable Polymer-Supported N-Heterocyclic Carbenes: Use in Organocatalysis
Journal of Polymer Science Part A: Polymer Chemistry, 2013Co-Authors: Paul Coupillaud, Joan Vignolle, Julien Pinaud, Nicolas Guidolin, Mareva Fevre, David Mecerreyes, Ellen Veaudecrenne, Daniel TatonAbstract:Synthesis of novel poly(ionic liquid)s, namely, poly(1-vinyl-3-alkylimidazolium hydrogen carbonate)s, denoted as poly([NHC(H)][HCO3])s or PVRImHCO(3), where R is an alkyl group (R=ethyl, butyl, phenylethyl, dodecyl), is described. Two distinct synthetic routes were explored. The first method is based on the free-radical polymerization (FRP) of 1-vinyl-3-alkylimidazolium monomers featuring a hydrogen carbonate counter anion (HCO3-), denoted as VRImHCO(3). The latter monomers were readily synthesized by alkylation of 1-vinylimidazole (VIm), followed by direct anion exchange of 1-vinyl-3-alkylimidazolium bromide monomers (VRImBr), using potassium hydrogen carbonate (KHCO3) in methanol at room temperature. Alternatively, the same anion exchange method could be applied onto FRP-derived poly(1-vinyl-3-alkylimidazolium bromide) precursors (PVRImBr). All PVRImHCO(3) salts proved air stable and could be manipulated without any particular precautions. They could serve as polymer-supported precatalysts to generate polymer-supported N-heterocyclic carbenes, referred to as poly(NHC)s, formally by a loss of H2CO3 (H2O +CO2) in solution. This was demonstrated through selected organocatalyzed reactions of molecular chemistry, known as being efficiently mediated by molecular NHC catalysts, including Benzoin Condensation, transesterification and cyanosilylation of aldehyde. Of particular interest, recycling of the polymer-supported precatalysts was possible by re-carboxylation of in situ generated poly(NHC)s. Organocatalyzed reactions could be performed with excellent yields, even after five catalytic cycles.
Julien Pinaud - One of the best experts on this subject based on the ideXlab platform.
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poly ionic liquid s based on imidazolium hydrogen carbonate monomer units as recyclable polymer supported n heterocyclic carbenes use in organocatalysis
Journal of Polymer Science Part A, 2013Co-Authors: Paul Coupillaud, Joan Vignolle, Julien Pinaud, Nicolas Guidolin, Mareva FevreAbstract:Synthesis of novel poly(ionic liquid)s, namely, poly(1-vinyl-3-alkylimidazolium hydrogen carbonate)s, denoted as poly([NHC(H)][HCO3])s or PVRImHCO3, where R is an alkyl group (R = ethyl, butyl, phenylethyl, dodecyl), is described. Two distinct synthetic routes were explored. The first method is based on the free-radical polymerization (FRP) of 1-vinyl-3-alkylimidazolium monomers featuring a hydrogen carbonate counter anion (HCO3−), denoted as VRImHCO3. The latter monomers were readily synthesized by alkylation of 1-vinylimidazole (VIm), followed by direct anion exchange of 1-vinyl-3-alkylimidazolium bromide monomers (VRImBr), using potassium hydrogen carbonate (KHCO3) in methanol at room temperature. Alternatively, the same anion exchange method could be applied onto FRP-derived poly(1-vinyl-3-alkylimidazolium bromide) precursors (PVRImBr). All PVRImHCO3 salts proved air stable and could be manipulated without any particular precautions. They could serve as polymer-supported precatalysts to generate polymer-supported N-heterocyclic carbenes, referred to as poly(NHC)s, formally by a loss of “H2CO3” (H2O +CO2) in solution. This was demonstrated through selected organocatalyzed reactions of molecular chemistry, known as being efficiently mediated by molecular NHC catalysts, including Benzoin Condensation, transesterification and cyanosilylation of aldehyde. Of particular interest, recycling of the polymer-supported precatalysts was possible by re-carboxylation of in situ generated poly(NHC)s. Organocatalyzed reactions could be performed with excellent yields, even after five catalytic cycles. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4530–4540
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Poly(ionic liquid)s Based on Imidazolium Hydrogen Carbonate Monomer Units as Recyclable Polymer-Supported N-Heterocyclic Carbenes: Use in Organocatalysis
Journal of Polymer Science Part A: Polymer Chemistry, 2013Co-Authors: Paul Coupillaud, Joan Vignolle, Julien Pinaud, Nicolas Guidolin, Mareva Fevre, David Mecerreyes, Ellen Veaudecrenne, Daniel TatonAbstract:Synthesis of novel poly(ionic liquid)s, namely, poly(1-vinyl-3-alkylimidazolium hydrogen carbonate)s, denoted as poly([NHC(H)][HCO3])s or PVRImHCO(3), where R is an alkyl group (R=ethyl, butyl, phenylethyl, dodecyl), is described. Two distinct synthetic routes were explored. The first method is based on the free-radical polymerization (FRP) of 1-vinyl-3-alkylimidazolium monomers featuring a hydrogen carbonate counter anion (HCO3-), denoted as VRImHCO(3). The latter monomers were readily synthesized by alkylation of 1-vinylimidazole (VIm), followed by direct anion exchange of 1-vinyl-3-alkylimidazolium bromide monomers (VRImBr), using potassium hydrogen carbonate (KHCO3) in methanol at room temperature. Alternatively, the same anion exchange method could be applied onto FRP-derived poly(1-vinyl-3-alkylimidazolium bromide) precursors (PVRImBr). All PVRImHCO(3) salts proved air stable and could be manipulated without any particular precautions. They could serve as polymer-supported precatalysts to generate polymer-supported N-heterocyclic carbenes, referred to as poly(NHC)s, formally by a loss of H2CO3 (H2O +CO2) in solution. This was demonstrated through selected organocatalyzed reactions of molecular chemistry, known as being efficiently mediated by molecular NHC catalysts, including Benzoin Condensation, transesterification and cyanosilylation of aldehyde. Of particular interest, recycling of the polymer-supported precatalysts was possible by re-carboxylation of in situ generated poly(NHC)s. Organocatalyzed reactions could be performed with excellent yields, even after five catalytic cycles.
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imidazol in ium hydrogen carbonates as a genuine source of n heterocyclic carbenes nhcs applications to the facile preparation of nhc metal complexes and to nhc organocatalyzed molecular and macromolecular syntheses
Journal of the American Chemical Society, 2012Co-Authors: Mareva Fevre, Joan Vignolle, Daniel Taton, Julien Pinaud, Yves Gnanou, Alexandre Leteneur, Karinne Miqueu, Jeanmarc SotiropoulosAbstract:Anion metathesis of imidazol(in)ium chlorides with KHCO3 afforded an easy one step access to air stable imidazol(in)ium hydrogen carbonates, denoted as [NHC(H)][HCO3]. In solution, these compounds were found to be in equilibrium with their corresponding imidazol(in)ium carboxylates, referred to as N-heterocyclic carbene (NHC)-CO2 adducts. The [NHC(H)][HCO3] salts were next shown to behave as masked NHCs, allowing for the NHC moiety to be readily transferred to both organic and organometallic substrates, without the need for dry and oxygen-free conditions. In addition, such [NHC(H)][HCO3] precursors were successfully investigated as precatalysts in two selected organocatalyzed reactions of molecular chemistry and polymer synthesis, namely, the Benzoin Condensation reaction and the ring-opening polymerization of d,l-lactide, respectively. The generation of NHCs from [NHC(H)][HCO3] precursors occurred via the formal loss of H2CO3via a concerted low energy pathway, as substantiated by Density Functional Theor...
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Imidazol(in)ium Hydrogen Carbonates as a Genuine Source of N-Heterocyclic Carbenes (NHCs): Applications to the Facile Preparation of NHC Metal Complexes and to NHC-Organocatalyzed Molecular and Macromolecular Syntheses
2012Co-Authors: Maréva Fèvre, Joan Vignolle, Daniel Taton, Julien Pinaud, Yves Gnanou, Alexandre Leteneur, Karinne Miqueu, Jeanmarc SotiropoulosAbstract:Anion metathesis of imidazol(in)ium chlorides with KHCO3 afforded an easy one step access to air stable imidazol(in)ium hydrogen carbonates, denoted as [NHC(H)][HCO3]. In solution, these compounds were found to be in equilibrium with their corresponding imidazol(in)ium carboxylates, referred to as N-heterocyclic carbene (NHC)-CO2 adducts. The [NHC(H)][HCO3] salts were next shown to behave as masked NHCs, allowing for the NHC moiety to be readily transferred to both organic and organometallic substrates, without the need for dry and oxygen-free conditions. In addition, such [NHC(H)][HCO3] precursors were successfully investigated as precatalysts in two selected organocatalyzed reactions of molecular chemistry and polymer synthesis, namely, the Benzoin Condensation reaction and the ring-opening polymerization of d,l-lactide, respectively. The generation of NHCs from [NHC(H)][HCO3] precursors occurred via the formal loss of H2CO3 via a concerted low energy pathway, as substantiated by Density Functional Theory (DFT) calculations
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Poly(N-heterocyclic-carbene)s and their CO(2) Adducts as Recyclable Polymer-Supported Organocatalysts for Benzoin Condensation and Transesterification Reactions
Macromolecules, 2011Co-Authors: Julien Pinaud, Joan Vignolle, Yves Gnanou, Daniel TatonAbstract:The synthesis of poly(N-heterocyclic carbene)s, denoted poly-(NHC)s, and of their poly(NHC-CO(2)) adducts for a use in organocatalysis is described. Poly(NHC)s were readily obtained in a three-step sequence of reactions, involving i) the free-radical polymerization of ionic liquid monomers, that is, 1-vinyl-3-alkylimidazolium-type monomers with bromide (Br(-)) as counteranion, followed by ii) anion exchange of Br(-) for bis(trifluoromethanesulfonyl)imide ((-)NTf2), of the poly(1-vinyl-3-alkylimidazolium bromide) precursors, affording poly(1-vinyl-3-alkylimidazolium bis(trifluorornethanesulfonyl)imide) derivatives, and iii) deprotonation of the latter polymeric ionic liquids with a strong base. Carbon dioxide (CO(2)) was found to reversibly react with poly(NHC)s forming relatively air-stable and thermolabile poly(NHC-CO(2)) adducts. Both poly(NHC)s and their poly(NHC-CO(2)) adducts were used as polymer-supported organic catalysts and precatalysts, respectively, in transesterification and Benzoin Condensation reactions under homogeneous conditions. Both types of polymer-supported NHCs were recycled and used several times, but the manipulation of poly(NHC)s like their molecular NHC analogues-was more complicated owing to their air and moisture sensitivity. In this regard, zwitterionic poly(NHC-CO(2)) adducts like their molecular NHC-CO(2) analogues could be easier manipulated than their bare poly(NHC) counterparts, providing good to excellent yields even after several organocatalytic cycles, in particular toward the transesterification reaction.
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functional mesoporous poly ionic liquid based copolymer monoliths from synthesis to catalysis and microporous carbon production
Polymer, 2014Co-Authors: Danuta Kuzmicz, Paul Coupillaud, Giordano Vendraminetto, Martina Ambrogi, Joan Vignolle, Yongjun Men, Daniel TatonAbstract:Abstract Ionic liquid-functionalized mesoporous polymeric networks with specific surface area up to 935 m 2 /g have been successfully synthesized one pot by solvothermal copolymerization of divinylbenzene and monomeric ionic liquids. The as-obtained polymers exhibit a monolithic structure featuring large pore volumes, an abundant mesoporosity and an adjustable content of ionic liquids. The effect of the reaction conditions on the pore structure has been studied in detail. These poly(ionic liquid)-based porous networks (PILPNs) have then been employed as precursors in two distinct applications, namely organocatalysis and production of microporous carbon monoliths. Selected organocatalyzed reactions, including carbonatation of propylene oxide by cycloaddition with carbon dioxide, Benzoin Condensation, and cyanosilylation of benzaldehyde have been readily triggered by PILPNs acting as crosslinked polymer-supported (pre)catalysts. The two latter reactions required the prior deprotonation of the imidazolium salt units with a strong base to successfully generate polymer-supported N -heterocyclic carbenes, referred to as poly(NHC)s. Facile recycling and reuse of polymer-supported (pre)catalysts was achieved by simple filtration owing to the heterogeneous reaction conditions. Furthermore, PILPNs could be easily converted into microporous carbon monoliths via CO 2 activation.
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Functional mesoporous poly(ionic liquid)-based copolymer monoliths: From synthesis to catalysis and microporous carbon production
Polymer (United Kingdom), 2014Co-Authors: Danuta Kuzmicz, Paul Coupillaud, Giordano Vendraminetto, Martina Ambrogi, Joan Vignolle, Daniel Taton, Yongjun Men, Jiayin YuanAbstract:Ionic liquid-functionalized mesoporous polymeric networks with specific surface area up to 935 m2/g have been successfully synthesized one pot by solvothermal copolymerization of divinylbenzene and monomeric ionic liquids. The as-obtained polymers exhibit a monolithic structure featuring large pore volumes, an abundant mesoporosity and an adjustable content of ionic liquids. The effect of the reaction conditions on the pore structure has been studied in detail. These poly(ionic liquid)-based porous networks (PILPNs) have then been employed as precursors in two distinct applications, namely organocatalysis and production of microporous carbon monoliths. Selected organocatalyzed reactions, including carbonatation of propylene oxide by cycloaddition with carbon dioxide, Benzoin Condensation, and cyanosilylation of benzaldehyde have been readily triggered by PILPNs acting as crosslinked polymer-supported (pre)catalysts. The two latter reactions required the prior deprotonation of the imidazolium salt units with a strong base to successfully generate polymer-supported N-heterocyclic carbenes, referred to as poly(NHC)s. Facile recycling and reuse of polymer-supported (pre)catalysts was achieved by simple filtration owing to the heterogeneous reaction conditions. Furthermore, PILPNs could be easily converted into microporous carbon monoliths via CO2activation. © 2014 Elsevier Ltd. All rights reserved.