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Mikhail A. Tlenkopatchev - One of the best experts on this subject based on the ideXlab platform.

  • synthesis and ionic transport of sulfonated ring opened polynorbornene based copolymers
    Polymer, 2011
    Co-Authors: Arlette A. Santiago, Mikhail A. Tlenkopatchev, Joel Vargas, Rubén Gaviño, Javier Cruzgomez, Mar Lopezgonzalez, Evaristo Riande
    Abstract:

    Abstract The N -pentafluorophenyl- exo-endo -norbornene-5,6-Dicarboximide ( 1a ) and N -phenyl- exo-endo -norbornene-5,6-Dicarboximide ( 1b ) monomers were synthesized and copolymerized via ring opening metathesis polymerization (ROMP) using bis(tricyclohexylphosphine)benzylidene ruthenium(IV) dichloride ( I ) and tricyclohexylphosphine[1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene][benzylidene]ruthenium dichloride ( II ). Experiments, at distinct monomer molar ratios, were carried out using catalyst I in order to determine the copolymerization reactivity constants by applying the Mayo-Lewis and Fineman-Ross methods. Moreover, both catalysts were used to produce random and block high molecular weight copolymers of 1a with 1b and 1a with norbornene ( NB ) which were further hydrogenated using a Wilkinson’s catalyst. Then, the saturated copolymers underwent a nucleophilic aromatic substitution by reacting with sodium 4-hydroxybenzenesulfonate dihydrate to generate new polynorbornene ionomers bearing fluorinated pendant benzenesulfonate groups. A thorough study on the electrochemical characteristics involving electromotive forces of concentration cells and proton conductivity of cation-exchange membranes based on a block copolymer of norbornene Dicarboximides containing structural units with phenyl and fluorinated pendant benzenesulfonate moieties is reported. The study of electromotive forces ( emf ) of concentration cells with the sulfonated membrane of copolymer 8 separating electrolyte solutions of different concentration indicate that the membranes exhibit high permselectivity to protons and sodium ions at moderately low concentrations. In principle, these results suggest that the membranes can be considered candidates for ionic separation applications.

  • polynorbornene with pentafluorophenyl imide side chain groups synthesis and sulfonation
    Journal of Polymer Science Part A, 2010
    Co-Authors: Arlette A. Santiago, Joel Vargas, Rubén Gaviño, Serguei Fomine, Mikhail A. Tlenkopatchev
    Abstract:

    The mixtures of exo-endo-monomers and isomerically pure endo-monomers of N-pentafluorophenyl-norbornene-5,6-Dicarboximide (2a) and N-phenyl-norbornene-5,6-Dicarboximide (2b) were synthesized and polymerized via ring opening metathesis polymerization using bis(tricyclohexylphosphine) benzylidene ruthenium (IV) dichloride (I) and tricyclohexylphosphine [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene][benzylidene] ruthenium dichloride (II). Ring opening metathesis polymerization of mixtures of exo-endo-monomers (2a) and (2b) and pure endo-2b gave the corresponding high molecular weights poly(N-pentafluorophenyl-norbornene-5,6-Dicarboximide) (3a) and poly(N-phenyl-norbornene-5,6-Dicarboximide) (3b). The isomerically pure endo-2a did not polymerize by I in these conditions, since I is the least active catalyst and endo-2a is the least active monomer because of the intramolecular complex formation between the Ru active center and the fluorine atom of ring-opened endo-2a on the one hand and steric hindrances caused by the pentafluorinated ring on the other. The quantitative hydrogenation of the polymer 3a, at room temperature and 115 bar, was achieved by a Wilkinson's catalyst. The new polynorbornene bearing highly fluorinated sulfonic acid groups (5) was obtained by the reaction of the hydrogenated poly(N-pentafluorophenyl-norbornene-5,6-Dicarboximide) (4) with sodium 4-hydroxybenzenesulfonate dihydrate. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2925–2933, 2010

  • Gas transport in membranes based on polynorbornenes with fluorinated Dicarboximide side moieties
    Journal of Membrane Science, 2010
    Co-Authors: Joel Vargas, Mikhail A. Tlenkopatchev, Arlette A. Santiago, Mar López-gonzález, Evaristo Riande
    Abstract:

    Abstract This work reports a comparative study of gas transport in membranes based on polynorbornenes and polyoxanorbornenes containing fluorinated Dicarboximide side moieties, specifically, poly( N -pentafluorophenyl- exo-endo- norbornene-5,6-Dicarboximide), poly( exo-N -pentafluorophenyl-7-oxanorbornene-5,6-Dicarboximide), poly( N -3,5-bis(trifluoromethyl)phenyl- exo-endo -norbornene-5,6-Dicarboximide) and a random copolymer of N -pentafluorophenyl- exo-endo -norbornene-5,6-Dicarboximide- co - N -phenyl- exo-endo -norbornene-5,6-Dicarboximide with 50/50 M composition. The gases studied were hydrogen, oxygen, nitrogen, carbon dioxide, methane, ethane, ethylene and propylene. The presence of fluorine atoms in the membranes increases their permeability in slight detriment of the permselectivity, the increase being higher for F–C bonds with carbon hybridization sp 3 than sp 2 . The substitution of the CH 2 groups of the norbornene moieties decreases the permeability as a consequence of the decrease of the solubility. A thorough study is carried out on the variation of the permeability coefficient and concentration of condensable gases, such as carbon dioxide and propylene, in the poly( N -pentafluorophenyl- exo-endo- norbornene-5,6-Dicarboximide) and poly( N -3,5-bis(trifluoromethyl)phenyl- exo-endo- norbornene-5,6-Dicarboximide) membranes finding that the values of the effective diffusion coefficient are similar to those obtained by the dual-mode model but significantly higher than those estimated by the time-lag from permeation results. The results also show that conditioning the membranes with condensable gases under high pressure increases the diffusivity.

  • Gas transport in membranes based on polynorbornenes with fluorinated Dicarboximide side moieties
    Journal of Membrane Science, 2010
    Co-Authors: Joel Vargas, Mikhail A. Tlenkopatchev, Arlette A. Santiago, Mar López-gonzález, Evaristo Riande
    Abstract:

    This work reports a comparative study of gas transport in membranes based on polynorbornenes\ud and polyoxanorbornenes containing fluorinated Dicarboximide side moieties,\ud specifically, poly(N-pentafluorophenyl-exo-endo-norbornene-5,6-Dicarboximide), poly(exo-Npentafluorophenyl-\ud 7-oxanorbornene-5,6-Dicarboximide), poly(N-3,5-bis(trifluoromethyl)phenylexo-\ud endo-norbornene-5,6-Dicarboximide) and a random copolymer of N-pentafluorophenyl-exo-endonorbornene-\ud 5,6-Dicarboximide-co-N-phenyl-exo-endo-norbornene-5,6-Dicarboximide with 50/50M\ud composition. The gases studied were hydrogen, oxygen, nitrogen, carbon dioxide, methane, ethane,\ud ethylene and propylene. The presence of fluorine atoms in the membranes increases their permeability\ud in slight detriment of the permselectivity, the increase being higher for F–C bonds with carbon\ud hybridization sp3 than sp2. The substitution of the CH2 groups of the norbornene moieties decreases\ud the permeability as a consequence of the decrease of the solubility. A thorough study is carried out on\ud the variation of the permeability coefficient and concentration of condensable gases, such as carbon\ud dioxide and propylene, in the poly(N-pentafluorophenyl-exo-endo-norbornene-5,6-Dicarboximide) and\ud poly(N-3,5-bis(trifluoromethyl)phenyl-exo-endo-norbornene-5,6-Dicarboximide) membranes finding\ud that the values of the effective diffusion coefficient are similar to those obtained by the dual-mode\ud model but significantly higher than those estimated by the time-lag from permeation results. The results\ud also show that conditioning the membranes with condensable gases under high pressure increases the\ud diffusivity.This work reports a comparative study of gas transport in membranes based on polynorbornenes\ud and polyoxanorbornenes containing fluorinated Dicarboximide side moieties,\ud specifically, poly(N-pentafluorophenyl-exo-endo-norbornene-5,6-Dicarboximide), poly(exo-Npentafluorophenyl-\ud 7-oxanorbornene-5,6-Dicarboximide), poly(N-3,5-bis(trifluoromethyl)phenylexo-\ud endo-norbornene-5,6-Dicarboximide) and a random copolymer of N-pentafluorophenyl-exo-endonorbornene-\ud 5,6-Dicarboximide-co-N-phenyl-exo-endo-norbornene-5,6-Dicarboximide with 50/50M\ud composition. The gases studied were hydrogen, oxygen, nitrogen, carbon dioxide, methane, ethane,\ud ethylene and propylene. The presence of fluorine atoms in the membranes increases their permeability\ud in slight detriment of the permselectivity, the increase being higher for F–C bonds with carbon\ud hybridization sp3 than sp2. The substitution of the CH2 groups of the norbornene moieties decreases\ud the permeability as a consequence of the decrease of the solubility. A thorough study is carried out on\ud the variation of the permeability coefficient and concentration of condensable gases, such as carbon\ud dioxide and propylene, in the poly(N-pentafluorophenyl-exo-endo-norbornene-5,6-Dicarboximide) and\ud poly(N-3,5-bis(trifluoromethyl)phenyl-exo-endo-norbornene-5,6-Dicarboximide) membranes finding\ud that the values of the effective diffusion coefficient are similar to those obtained by the dual-mode\ud model but significantly higher than those estimated by the time-lag from permeation results. The results\ud also show that conditioning the membranes with condensable gases under high pressure increases the\ud diffusivity.Peer reviewe

  • The effect of fluorine atoms on gas transport properties of new polynorbornene Dicarboximides
    Journal of Fluorine Chemistry, 2009
    Co-Authors: Joel Vargas, Mikhail A. Tlenkopatchev, Arlette A. Santiago, Araceli Martínez, Rubén Gaviño, Manuel Aguilar-vega
    Abstract:

    Abstract The new N -4-trifluoromethylphenyl-norbornene-5,6-Dicarboximide ( 2a ) and N -3,5-bis(trifluoromethyl)phenyl-norbornene-5,6-Dicarboximide ( 2b ) mixtures of exo and endo monomers were synthesized and polymerized via ring opening metathesis polymerization (ROMP) using bis(tricyclohexylphosphine) benzylidene ruthenium(IV) dichloride ( I ) and tricyclohexylphosphine [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene][benzylidene] ruthenium dichloride ( II ) to produce the corresponding polynorbornene Dicarboximides Poly-2a and Poly-2b , respectively. The transport of five gases He, N 2 , O 2 , CO 2 and CH 4 across membranes prepared from Poly-2a was determined at 35 °C using a constant volume permeation cell. The gas transport properties of the fluorine containing polymer Poly-2a were compared with those found for membranes from non-fluorinated poly( N -phenyl- exo-endo -norbornene-5,6-Dicarboximide) ( P-PhNDI ). Gas permeability, diffusion and solubility coefficients of the fluorine containing polynorbornene Poly-2a were up to an order of magnitude larger than those of the non-fluorinated one. Poly-2a was found to have one of the largest gas transport coefficients reported to date in glassy polynorbornene Dicarboximides.

Frank Würthner - One of the best experts on this subject based on the ideXlab platform.

  • 1 1 bi 2 naphthol 4 5 Dicarboximide s blue emissive axially chiral scaffolds with aggregation enhanced emission properties
    Organic chemistry frontiers, 2019
    Co-Authors: Meng-ting Chen, Yang Zhang, Myroslav O. Vysotsky, Joachim O. Lindner, Mei-jin Lin, Frank Würthner
    Abstract:

    1,1′-Binaphthol (BINOL) is a versatile chiral reagent with widespread applications in asymmetric catalysis and fluorescent bio-sensing and imaging. However, unsubstituted BINOLs exhibit only weak and short-wavelength emission, limiting their scope for the latter applications. Herein, we report axially chiral 1,1′-bi(2-naphthol-4,5-Dicarboximide)s which show two reversible reductions, bright blue light fluorescence with fluorescence quantum yields up to 0.67, and aggregation-enhanced emission characteristics. Single crystal X-ray analysis revealed an intriguing double helical supramolecular polymer motif formed by π–π stacking interactions between 2-naphthol-4,5-Dicarboximide units. The enantiomers of racemic 1,1′-bi(2-naphthol-4,5-Dicarboximide)s were resolved on chiral columns and studied by CD spectroscopy.

  • 1,1′-Bi(2-naphthol-4,5-Dicarboximide)s: blue emissive axially chiral scaffolds with aggregation-enhanced emission properties
    Organic Chemistry Frontiers, 2019
    Co-Authors: Meng-ting Chen, Yang Zhang, Myroslav O. Vysotsky, Joachim O. Lindner, Mei-jin Lin, Frank Würthner
    Abstract:

    1,1′-Binaphthol (BINOL) is a versatile chiral reagent with widespread applications in asymmetric catalysis and fluorescent bio-sensing and imaging. However, unsubstituted BINOLs exhibit only weak and short-wavelength emission, limiting their scope for the latter applications. Herein, we report axially chiral 1,1′-bi(2-naphthol-4,5-Dicarboximide)s which show two reversible reductions, bright blue light fluorescence with fluorescence quantum yields up to 0.67, and aggregation-enhanced emission characteristics. Single crystal X-ray analysis revealed an intriguing double helical supramolecular polymer motif formed by π–π stacking interactions between 2-naphthol-4,5-Dicarboximide units. The enantiomers of racemic 1,1′-bi(2-naphthol-4,5-Dicarboximide)s were resolved on chiral columns and studied by CD spectroscopy.

  • A General Synthetic Route to Polycyclic Aromatic Dicarboximides by Palladium-Catalyzed Annulation Reaction.
    The Journal of organic chemistry, 2018
    Co-Authors: Kazutaka Shoyama, Magnus Mahl, Sabine Seifert, Frank Würthner
    Abstract:

    Here we report a general method for the synthesis of polycyclic aromatic Dicarboximides (PADIs) by palladium-catalyzed annulation of naphthalene Dicarboximide to different types of aromatic substrates. Reaction conditions were optimized by systematic variation of ligand, solvent, and additive. It was shown that solvent has a decisive effect on the yield of the reaction products, and thus 1-chloronaphthalene as solvent afforded the highest yield. By applying the optimized reaction conditions, a broad series of planar carbo- and heterocycle containing PADIs were synthesized in up to 97% yield. Moreover, this approach could be applied to curved aromatic scaffold to achieve the respective bowl-shaped PADI. Two-fold annulation was accomplished by employing arene diboronic esters, affording polycyclic aromatic bis(Dicarboximides). The optical and electrochemical properties of this broad series of PADIs were explored as well.

  • Electron-Poor Bowl-Shaped Polycyclic Aromatic Dicarboximides: Synthesis, Crystal Structures, and Optical and Redox Properties
    Organic letters, 2017
    Co-Authors: Kazutaka Shoyama, David Schmidt, Magnus Mahl, Frank Würthner
    Abstract:

    Two new bowl-shaped polycyclic aromatic hydrocarbons, based on corannulene and naphthalene Dicarboximide, are synthesized by an improved Suzuki–Miyaura cross-coupling and C–H arylation cascade reaction. Crystallographic analyses confirm structural assignments and provide insight into molecular interactions in the solid state. The new bowl-shaped molecules show reversible oxidation and reduction, intense visible range absorption, and high fluorescence quantum yields. These molecules can be considered bowl-shaped congeners of planar perylene Dicarboximides.

Joel Vargas - One of the best experts on this subject based on the ideXlab platform.

  • synthesis and ionic transport of sulfonated ring opened polynorbornene based copolymers
    Polymer, 2011
    Co-Authors: Arlette A. Santiago, Mikhail A. Tlenkopatchev, Joel Vargas, Rubén Gaviño, Javier Cruzgomez, Mar Lopezgonzalez, Evaristo Riande
    Abstract:

    Abstract The N -pentafluorophenyl- exo-endo -norbornene-5,6-Dicarboximide ( 1a ) and N -phenyl- exo-endo -norbornene-5,6-Dicarboximide ( 1b ) monomers were synthesized and copolymerized via ring opening metathesis polymerization (ROMP) using bis(tricyclohexylphosphine)benzylidene ruthenium(IV) dichloride ( I ) and tricyclohexylphosphine[1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene][benzylidene]ruthenium dichloride ( II ). Experiments, at distinct monomer molar ratios, were carried out using catalyst I in order to determine the copolymerization reactivity constants by applying the Mayo-Lewis and Fineman-Ross methods. Moreover, both catalysts were used to produce random and block high molecular weight copolymers of 1a with 1b and 1a with norbornene ( NB ) which were further hydrogenated using a Wilkinson’s catalyst. Then, the saturated copolymers underwent a nucleophilic aromatic substitution by reacting with sodium 4-hydroxybenzenesulfonate dihydrate to generate new polynorbornene ionomers bearing fluorinated pendant benzenesulfonate groups. A thorough study on the electrochemical characteristics involving electromotive forces of concentration cells and proton conductivity of cation-exchange membranes based on a block copolymer of norbornene Dicarboximides containing structural units with phenyl and fluorinated pendant benzenesulfonate moieties is reported. The study of electromotive forces ( emf ) of concentration cells with the sulfonated membrane of copolymer 8 separating electrolyte solutions of different concentration indicate that the membranes exhibit high permselectivity to protons and sodium ions at moderately low concentrations. In principle, these results suggest that the membranes can be considered candidates for ionic separation applications.

  • polynorbornene with pentafluorophenyl imide side chain groups synthesis and sulfonation
    Journal of Polymer Science Part A, 2010
    Co-Authors: Arlette A. Santiago, Joel Vargas, Rubén Gaviño, Serguei Fomine, Mikhail A. Tlenkopatchev
    Abstract:

    The mixtures of exo-endo-monomers and isomerically pure endo-monomers of N-pentafluorophenyl-norbornene-5,6-Dicarboximide (2a) and N-phenyl-norbornene-5,6-Dicarboximide (2b) were synthesized and polymerized via ring opening metathesis polymerization using bis(tricyclohexylphosphine) benzylidene ruthenium (IV) dichloride (I) and tricyclohexylphosphine [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene][benzylidene] ruthenium dichloride (II). Ring opening metathesis polymerization of mixtures of exo-endo-monomers (2a) and (2b) and pure endo-2b gave the corresponding high molecular weights poly(N-pentafluorophenyl-norbornene-5,6-Dicarboximide) (3a) and poly(N-phenyl-norbornene-5,6-Dicarboximide) (3b). The isomerically pure endo-2a did not polymerize by I in these conditions, since I is the least active catalyst and endo-2a is the least active monomer because of the intramolecular complex formation between the Ru active center and the fluorine atom of ring-opened endo-2a on the one hand and steric hindrances caused by the pentafluorinated ring on the other. The quantitative hydrogenation of the polymer 3a, at room temperature and 115 bar, was achieved by a Wilkinson's catalyst. The new polynorbornene bearing highly fluorinated sulfonic acid groups (5) was obtained by the reaction of the hydrogenated poly(N-pentafluorophenyl-norbornene-5,6-Dicarboximide) (4) with sodium 4-hydroxybenzenesulfonate dihydrate. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2925–2933, 2010

  • Gas transport in membranes based on polynorbornenes with fluorinated Dicarboximide side moieties
    Journal of Membrane Science, 2010
    Co-Authors: Joel Vargas, Mikhail A. Tlenkopatchev, Arlette A. Santiago, Mar López-gonzález, Evaristo Riande
    Abstract:

    Abstract This work reports a comparative study of gas transport in membranes based on polynorbornenes and polyoxanorbornenes containing fluorinated Dicarboximide side moieties, specifically, poly( N -pentafluorophenyl- exo-endo- norbornene-5,6-Dicarboximide), poly( exo-N -pentafluorophenyl-7-oxanorbornene-5,6-Dicarboximide), poly( N -3,5-bis(trifluoromethyl)phenyl- exo-endo -norbornene-5,6-Dicarboximide) and a random copolymer of N -pentafluorophenyl- exo-endo -norbornene-5,6-Dicarboximide- co - N -phenyl- exo-endo -norbornene-5,6-Dicarboximide with 50/50 M composition. The gases studied were hydrogen, oxygen, nitrogen, carbon dioxide, methane, ethane, ethylene and propylene. The presence of fluorine atoms in the membranes increases their permeability in slight detriment of the permselectivity, the increase being higher for F–C bonds with carbon hybridization sp 3 than sp 2 . The substitution of the CH 2 groups of the norbornene moieties decreases the permeability as a consequence of the decrease of the solubility. A thorough study is carried out on the variation of the permeability coefficient and concentration of condensable gases, such as carbon dioxide and propylene, in the poly( N -pentafluorophenyl- exo-endo- norbornene-5,6-Dicarboximide) and poly( N -3,5-bis(trifluoromethyl)phenyl- exo-endo- norbornene-5,6-Dicarboximide) membranes finding that the values of the effective diffusion coefficient are similar to those obtained by the dual-mode model but significantly higher than those estimated by the time-lag from permeation results. The results also show that conditioning the membranes with condensable gases under high pressure increases the diffusivity.

  • Gas transport in membranes based on polynorbornenes with fluorinated Dicarboximide side moieties
    Journal of Membrane Science, 2010
    Co-Authors: Joel Vargas, Mikhail A. Tlenkopatchev, Arlette A. Santiago, Mar López-gonzález, Evaristo Riande
    Abstract:

    This work reports a comparative study of gas transport in membranes based on polynorbornenes\ud and polyoxanorbornenes containing fluorinated Dicarboximide side moieties,\ud specifically, poly(N-pentafluorophenyl-exo-endo-norbornene-5,6-Dicarboximide), poly(exo-Npentafluorophenyl-\ud 7-oxanorbornene-5,6-Dicarboximide), poly(N-3,5-bis(trifluoromethyl)phenylexo-\ud endo-norbornene-5,6-Dicarboximide) and a random copolymer of N-pentafluorophenyl-exo-endonorbornene-\ud 5,6-Dicarboximide-co-N-phenyl-exo-endo-norbornene-5,6-Dicarboximide with 50/50M\ud composition. The gases studied were hydrogen, oxygen, nitrogen, carbon dioxide, methane, ethane,\ud ethylene and propylene. The presence of fluorine atoms in the membranes increases their permeability\ud in slight detriment of the permselectivity, the increase being higher for F–C bonds with carbon\ud hybridization sp3 than sp2. The substitution of the CH2 groups of the norbornene moieties decreases\ud the permeability as a consequence of the decrease of the solubility. A thorough study is carried out on\ud the variation of the permeability coefficient and concentration of condensable gases, such as carbon\ud dioxide and propylene, in the poly(N-pentafluorophenyl-exo-endo-norbornene-5,6-Dicarboximide) and\ud poly(N-3,5-bis(trifluoromethyl)phenyl-exo-endo-norbornene-5,6-Dicarboximide) membranes finding\ud that the values of the effective diffusion coefficient are similar to those obtained by the dual-mode\ud model but significantly higher than those estimated by the time-lag from permeation results. The results\ud also show that conditioning the membranes with condensable gases under high pressure increases the\ud diffusivity.This work reports a comparative study of gas transport in membranes based on polynorbornenes\ud and polyoxanorbornenes containing fluorinated Dicarboximide side moieties,\ud specifically, poly(N-pentafluorophenyl-exo-endo-norbornene-5,6-Dicarboximide), poly(exo-Npentafluorophenyl-\ud 7-oxanorbornene-5,6-Dicarboximide), poly(N-3,5-bis(trifluoromethyl)phenylexo-\ud endo-norbornene-5,6-Dicarboximide) and a random copolymer of N-pentafluorophenyl-exo-endonorbornene-\ud 5,6-Dicarboximide-co-N-phenyl-exo-endo-norbornene-5,6-Dicarboximide with 50/50M\ud composition. The gases studied were hydrogen, oxygen, nitrogen, carbon dioxide, methane, ethane,\ud ethylene and propylene. The presence of fluorine atoms in the membranes increases their permeability\ud in slight detriment of the permselectivity, the increase being higher for F–C bonds with carbon\ud hybridization sp3 than sp2. The substitution of the CH2 groups of the norbornene moieties decreases\ud the permeability as a consequence of the decrease of the solubility. A thorough study is carried out on\ud the variation of the permeability coefficient and concentration of condensable gases, such as carbon\ud dioxide and propylene, in the poly(N-pentafluorophenyl-exo-endo-norbornene-5,6-Dicarboximide) and\ud poly(N-3,5-bis(trifluoromethyl)phenyl-exo-endo-norbornene-5,6-Dicarboximide) membranes finding\ud that the values of the effective diffusion coefficient are similar to those obtained by the dual-mode\ud model but significantly higher than those estimated by the time-lag from permeation results. The results\ud also show that conditioning the membranes with condensable gases under high pressure increases the\ud diffusivity.Peer reviewe

  • The effect of fluorine atoms on gas transport properties of new polynorbornene Dicarboximides
    Journal of Fluorine Chemistry, 2009
    Co-Authors: Joel Vargas, Mikhail A. Tlenkopatchev, Arlette A. Santiago, Araceli Martínez, Rubén Gaviño, Manuel Aguilar-vega
    Abstract:

    Abstract The new N -4-trifluoromethylphenyl-norbornene-5,6-Dicarboximide ( 2a ) and N -3,5-bis(trifluoromethyl)phenyl-norbornene-5,6-Dicarboximide ( 2b ) mixtures of exo and endo monomers were synthesized and polymerized via ring opening metathesis polymerization (ROMP) using bis(tricyclohexylphosphine) benzylidene ruthenium(IV) dichloride ( I ) and tricyclohexylphosphine [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene][benzylidene] ruthenium dichloride ( II ) to produce the corresponding polynorbornene Dicarboximides Poly-2a and Poly-2b , respectively. The transport of five gases He, N 2 , O 2 , CO 2 and CH 4 across membranes prepared from Poly-2a was determined at 35 °C using a constant volume permeation cell. The gas transport properties of the fluorine containing polymer Poly-2a were compared with those found for membranes from non-fluorinated poly( N -phenyl- exo-endo -norbornene-5,6-Dicarboximide) ( P-PhNDI ). Gas permeability, diffusion and solubility coefficients of the fluorine containing polynorbornene Poly-2a were up to an order of magnitude larger than those of the non-fluorinated one. Poly-2a was found to have one of the largest gas transport coefficients reported to date in glassy polynorbornene Dicarboximides.

Arlette A. Santiago - One of the best experts on this subject based on the ideXlab platform.

  • synthesis and ionic transport of sulfonated ring opened polynorbornene based copolymers
    Polymer, 2011
    Co-Authors: Arlette A. Santiago, Mikhail A. Tlenkopatchev, Joel Vargas, Rubén Gaviño, Javier Cruzgomez, Mar Lopezgonzalez, Evaristo Riande
    Abstract:

    Abstract The N -pentafluorophenyl- exo-endo -norbornene-5,6-Dicarboximide ( 1a ) and N -phenyl- exo-endo -norbornene-5,6-Dicarboximide ( 1b ) monomers were synthesized and copolymerized via ring opening metathesis polymerization (ROMP) using bis(tricyclohexylphosphine)benzylidene ruthenium(IV) dichloride ( I ) and tricyclohexylphosphine[1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene][benzylidene]ruthenium dichloride ( II ). Experiments, at distinct monomer molar ratios, were carried out using catalyst I in order to determine the copolymerization reactivity constants by applying the Mayo-Lewis and Fineman-Ross methods. Moreover, both catalysts were used to produce random and block high molecular weight copolymers of 1a with 1b and 1a with norbornene ( NB ) which were further hydrogenated using a Wilkinson’s catalyst. Then, the saturated copolymers underwent a nucleophilic aromatic substitution by reacting with sodium 4-hydroxybenzenesulfonate dihydrate to generate new polynorbornene ionomers bearing fluorinated pendant benzenesulfonate groups. A thorough study on the electrochemical characteristics involving electromotive forces of concentration cells and proton conductivity of cation-exchange membranes based on a block copolymer of norbornene Dicarboximides containing structural units with phenyl and fluorinated pendant benzenesulfonate moieties is reported. The study of electromotive forces ( emf ) of concentration cells with the sulfonated membrane of copolymer 8 separating electrolyte solutions of different concentration indicate that the membranes exhibit high permselectivity to protons and sodium ions at moderately low concentrations. In principle, these results suggest that the membranes can be considered candidates for ionic separation applications.

  • polynorbornene with pentafluorophenyl imide side chain groups synthesis and sulfonation
    Journal of Polymer Science Part A, 2010
    Co-Authors: Arlette A. Santiago, Joel Vargas, Rubén Gaviño, Serguei Fomine, Mikhail A. Tlenkopatchev
    Abstract:

    The mixtures of exo-endo-monomers and isomerically pure endo-monomers of N-pentafluorophenyl-norbornene-5,6-Dicarboximide (2a) and N-phenyl-norbornene-5,6-Dicarboximide (2b) were synthesized and polymerized via ring opening metathesis polymerization using bis(tricyclohexylphosphine) benzylidene ruthenium (IV) dichloride (I) and tricyclohexylphosphine [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene][benzylidene] ruthenium dichloride (II). Ring opening metathesis polymerization of mixtures of exo-endo-monomers (2a) and (2b) and pure endo-2b gave the corresponding high molecular weights poly(N-pentafluorophenyl-norbornene-5,6-Dicarboximide) (3a) and poly(N-phenyl-norbornene-5,6-Dicarboximide) (3b). The isomerically pure endo-2a did not polymerize by I in these conditions, since I is the least active catalyst and endo-2a is the least active monomer because of the intramolecular complex formation between the Ru active center and the fluorine atom of ring-opened endo-2a on the one hand and steric hindrances caused by the pentafluorinated ring on the other. The quantitative hydrogenation of the polymer 3a, at room temperature and 115 bar, was achieved by a Wilkinson's catalyst. The new polynorbornene bearing highly fluorinated sulfonic acid groups (5) was obtained by the reaction of the hydrogenated poly(N-pentafluorophenyl-norbornene-5,6-Dicarboximide) (4) with sodium 4-hydroxybenzenesulfonate dihydrate. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2925–2933, 2010

  • Gas transport in membranes based on polynorbornenes with fluorinated Dicarboximide side moieties
    Journal of Membrane Science, 2010
    Co-Authors: Joel Vargas, Mikhail A. Tlenkopatchev, Arlette A. Santiago, Mar López-gonzález, Evaristo Riande
    Abstract:

    Abstract This work reports a comparative study of gas transport in membranes based on polynorbornenes and polyoxanorbornenes containing fluorinated Dicarboximide side moieties, specifically, poly( N -pentafluorophenyl- exo-endo- norbornene-5,6-Dicarboximide), poly( exo-N -pentafluorophenyl-7-oxanorbornene-5,6-Dicarboximide), poly( N -3,5-bis(trifluoromethyl)phenyl- exo-endo -norbornene-5,6-Dicarboximide) and a random copolymer of N -pentafluorophenyl- exo-endo -norbornene-5,6-Dicarboximide- co - N -phenyl- exo-endo -norbornene-5,6-Dicarboximide with 50/50 M composition. The gases studied were hydrogen, oxygen, nitrogen, carbon dioxide, methane, ethane, ethylene and propylene. The presence of fluorine atoms in the membranes increases their permeability in slight detriment of the permselectivity, the increase being higher for F–C bonds with carbon hybridization sp 3 than sp 2 . The substitution of the CH 2 groups of the norbornene moieties decreases the permeability as a consequence of the decrease of the solubility. A thorough study is carried out on the variation of the permeability coefficient and concentration of condensable gases, such as carbon dioxide and propylene, in the poly( N -pentafluorophenyl- exo-endo- norbornene-5,6-Dicarboximide) and poly( N -3,5-bis(trifluoromethyl)phenyl- exo-endo- norbornene-5,6-Dicarboximide) membranes finding that the values of the effective diffusion coefficient are similar to those obtained by the dual-mode model but significantly higher than those estimated by the time-lag from permeation results. The results also show that conditioning the membranes with condensable gases under high pressure increases the diffusivity.

  • Gas transport in membranes based on polynorbornenes with fluorinated Dicarboximide side moieties
    Journal of Membrane Science, 2010
    Co-Authors: Joel Vargas, Mikhail A. Tlenkopatchev, Arlette A. Santiago, Mar López-gonzález, Evaristo Riande
    Abstract:

    This work reports a comparative study of gas transport in membranes based on polynorbornenes\ud and polyoxanorbornenes containing fluorinated Dicarboximide side moieties,\ud specifically, poly(N-pentafluorophenyl-exo-endo-norbornene-5,6-Dicarboximide), poly(exo-Npentafluorophenyl-\ud 7-oxanorbornene-5,6-Dicarboximide), poly(N-3,5-bis(trifluoromethyl)phenylexo-\ud endo-norbornene-5,6-Dicarboximide) and a random copolymer of N-pentafluorophenyl-exo-endonorbornene-\ud 5,6-Dicarboximide-co-N-phenyl-exo-endo-norbornene-5,6-Dicarboximide with 50/50M\ud composition. The gases studied were hydrogen, oxygen, nitrogen, carbon dioxide, methane, ethane,\ud ethylene and propylene. The presence of fluorine atoms in the membranes increases their permeability\ud in slight detriment of the permselectivity, the increase being higher for F–C bonds with carbon\ud hybridization sp3 than sp2. The substitution of the CH2 groups of the norbornene moieties decreases\ud the permeability as a consequence of the decrease of the solubility. A thorough study is carried out on\ud the variation of the permeability coefficient and concentration of condensable gases, such as carbon\ud dioxide and propylene, in the poly(N-pentafluorophenyl-exo-endo-norbornene-5,6-Dicarboximide) and\ud poly(N-3,5-bis(trifluoromethyl)phenyl-exo-endo-norbornene-5,6-Dicarboximide) membranes finding\ud that the values of the effective diffusion coefficient are similar to those obtained by the dual-mode\ud model but significantly higher than those estimated by the time-lag from permeation results. The results\ud also show that conditioning the membranes with condensable gases under high pressure increases the\ud diffusivity.This work reports a comparative study of gas transport in membranes based on polynorbornenes\ud and polyoxanorbornenes containing fluorinated Dicarboximide side moieties,\ud specifically, poly(N-pentafluorophenyl-exo-endo-norbornene-5,6-Dicarboximide), poly(exo-Npentafluorophenyl-\ud 7-oxanorbornene-5,6-Dicarboximide), poly(N-3,5-bis(trifluoromethyl)phenylexo-\ud endo-norbornene-5,6-Dicarboximide) and a random copolymer of N-pentafluorophenyl-exo-endonorbornene-\ud 5,6-Dicarboximide-co-N-phenyl-exo-endo-norbornene-5,6-Dicarboximide with 50/50M\ud composition. The gases studied were hydrogen, oxygen, nitrogen, carbon dioxide, methane, ethane,\ud ethylene and propylene. The presence of fluorine atoms in the membranes increases their permeability\ud in slight detriment of the permselectivity, the increase being higher for F–C bonds with carbon\ud hybridization sp3 than sp2. The substitution of the CH2 groups of the norbornene moieties decreases\ud the permeability as a consequence of the decrease of the solubility. A thorough study is carried out on\ud the variation of the permeability coefficient and concentration of condensable gases, such as carbon\ud dioxide and propylene, in the poly(N-pentafluorophenyl-exo-endo-norbornene-5,6-Dicarboximide) and\ud poly(N-3,5-bis(trifluoromethyl)phenyl-exo-endo-norbornene-5,6-Dicarboximide) membranes finding\ud that the values of the effective diffusion coefficient are similar to those obtained by the dual-mode\ud model but significantly higher than those estimated by the time-lag from permeation results. The results\ud also show that conditioning the membranes with condensable gases under high pressure increases the\ud diffusivity.Peer reviewe

  • The effect of fluorine atoms on gas transport properties of new polynorbornene Dicarboximides
    Journal of Fluorine Chemistry, 2009
    Co-Authors: Joel Vargas, Mikhail A. Tlenkopatchev, Arlette A. Santiago, Araceli Martínez, Rubén Gaviño, Manuel Aguilar-vega
    Abstract:

    Abstract The new N -4-trifluoromethylphenyl-norbornene-5,6-Dicarboximide ( 2a ) and N -3,5-bis(trifluoromethyl)phenyl-norbornene-5,6-Dicarboximide ( 2b ) mixtures of exo and endo monomers were synthesized and polymerized via ring opening metathesis polymerization (ROMP) using bis(tricyclohexylphosphine) benzylidene ruthenium(IV) dichloride ( I ) and tricyclohexylphosphine [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene][benzylidene] ruthenium dichloride ( II ) to produce the corresponding polynorbornene Dicarboximides Poly-2a and Poly-2b , respectively. The transport of five gases He, N 2 , O 2 , CO 2 and CH 4 across membranes prepared from Poly-2a was determined at 35 °C using a constant volume permeation cell. The gas transport properties of the fluorine containing polymer Poly-2a were compared with those found for membranes from non-fluorinated poly( N -phenyl- exo-endo -norbornene-5,6-Dicarboximide) ( P-PhNDI ). Gas permeability, diffusion and solubility coefficients of the fluorine containing polynorbornene Poly-2a were up to an order of magnitude larger than those of the non-fluorinated one. Poly-2a was found to have one of the largest gas transport coefficients reported to date in glassy polynorbornene Dicarboximides.

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  • 1 1 bi 2 naphthol 4 5 Dicarboximide s blue emissive axially chiral scaffolds with aggregation enhanced emission properties
    Organic chemistry frontiers, 2019
    Co-Authors: Meng-ting Chen, Yang Zhang, Myroslav O. Vysotsky, Joachim O. Lindner, Mei-jin Lin, Frank Würthner
    Abstract:

    1,1′-Binaphthol (BINOL) is a versatile chiral reagent with widespread applications in asymmetric catalysis and fluorescent bio-sensing and imaging. However, unsubstituted BINOLs exhibit only weak and short-wavelength emission, limiting their scope for the latter applications. Herein, we report axially chiral 1,1′-bi(2-naphthol-4,5-Dicarboximide)s which show two reversible reductions, bright blue light fluorescence with fluorescence quantum yields up to 0.67, and aggregation-enhanced emission characteristics. Single crystal X-ray analysis revealed an intriguing double helical supramolecular polymer motif formed by π–π stacking interactions between 2-naphthol-4,5-Dicarboximide units. The enantiomers of racemic 1,1′-bi(2-naphthol-4,5-Dicarboximide)s were resolved on chiral columns and studied by CD spectroscopy.

  • 1,1′-Bi(2-naphthol-4,5-Dicarboximide)s: blue emissive axially chiral scaffolds with aggregation-enhanced emission properties
    Organic Chemistry Frontiers, 2019
    Co-Authors: Meng-ting Chen, Yang Zhang, Myroslav O. Vysotsky, Joachim O. Lindner, Mei-jin Lin, Frank Würthner
    Abstract:

    1,1′-Binaphthol (BINOL) is a versatile chiral reagent with widespread applications in asymmetric catalysis and fluorescent bio-sensing and imaging. However, unsubstituted BINOLs exhibit only weak and short-wavelength emission, limiting their scope for the latter applications. Herein, we report axially chiral 1,1′-bi(2-naphthol-4,5-Dicarboximide)s which show two reversible reductions, bright blue light fluorescence with fluorescence quantum yields up to 0.67, and aggregation-enhanced emission characteristics. Single crystal X-ray analysis revealed an intriguing double helical supramolecular polymer motif formed by π–π stacking interactions between 2-naphthol-4,5-Dicarboximide units. The enantiomers of racemic 1,1′-bi(2-naphthol-4,5-Dicarboximide)s were resolved on chiral columns and studied by CD spectroscopy.