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H H Horhold - One of the best experts on this subject based on the ideXlab platform.
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investigation of poly arylene vinylene s 41 synthesis of soluble dialkoxy substituted poly phenylene alkenylidene s by applying the Horner Reaction for condensation polymerization
Macromolecular Chemistry and Physics, 1999Co-Authors: S Pfeiffer, H H HorholdAbstract:Soluble poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,2-ethenylene] (MEH-PPV) and its alternating copolymer poly[2,5-dimethoxy-1,4-phenylene-1,2-ethenylene-2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,2-ethenylene] (M3EH-PPV) were successfully synthesized by condensation polymerization of substituted terephthalaldehydes with substituted xylylene bisphosphonates via the Horner Reaction. This polycondensation method was also applied to the synthesis of the analogous poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,3-butadiene-1,4-diyl] (MEH-PPB), which contains a 1,3-butadiene instead of a vinylene unit. The optical data of MEH-PPV and M3EH-PPV (solid film, abs. λ max 484 nm, em. λ max 589 nm) are consistent with those previously reported for MEH-PPV from the dehydrohalogenation route. In comparison to MEH-PPV, the longer alkenylene sequence of MEH-PPB exhibits a slight red shift in its absorption and fluorescence spectra (abs. λ max 502 nm, em. λ max 604 nm). All three polyphenylene alkenylidenes (MEH-PPV, M3EH-PPV, and MEH-PPB) are completely soluble in common solvents. They are well-defined conjugated polymers of high molecular weight (M w > 20000) and possess all-trans structure. Optical quality solid films are easily prepared from these polymers by solution processing. Blends with phenyl-substituted PPV derivatives can also be prepared in this way. This combination of properties is highly desirable for many light-emitting, nonlinear optical, and photoelectrical applications.
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Investigation of poly(arylene vinylene)s, 41. Synthesis of soluble dialkoxy‐substituted poly(phenylene alkenylidene)s by applying the Horner‐Reaction for condensation polymerization
Macromolecular Chemistry and Physics, 1999Co-Authors: S Pfeiffer, H H HorholdAbstract:Soluble poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,2-ethenylene] (MEH-PPV) and its alternating copolymer poly[2,5-dimethoxy-1,4-phenylene-1,2-ethenylene-2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,2-ethenylene] (M3EH-PPV) were successfully synthesized by condensation polymerization of substituted terephthalaldehydes with substituted xylylene bisphosphonates via the Horner Reaction. This polycondensation method was also applied to the synthesis of the analogous poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,3-butadiene-1,4-diyl] (MEH-PPB), which contains a 1,3-butadiene instead of a vinylene unit. The optical data of MEH-PPV and M3EH-PPV (solid film, abs. λ max 484 nm, em. λ max 589 nm) are consistent with those previously reported for MEH-PPV from the dehydrohalogenation route. In comparison to MEH-PPV, the longer alkenylene sequence of MEH-PPB exhibits a slight red shift in its absorption and fluorescence spectra (abs. λ max 502 nm, em. λ max 604 nm). All three polyphenylene alkenylidenes (MEH-PPV, M3EH-PPV, and MEH-PPB) are completely soluble in common solvents. They are well-defined conjugated polymers of high molecular weight (M w > 20000) and possess all-trans structure. Optical quality solid films are easily prepared from these polymers by solution processing. Blends with phenyl-substituted PPV derivatives can also be prepared in this way. This combination of properties is highly desirable for many light-emitting, nonlinear optical, and photoelectrical applications.
Olivier Piva - One of the best experts on this subject based on the ideXlab platform.
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Tandem Michael–Wittig–Horner Reaction: Application to the Synthesis of Bisabolanes
Synthetic Communications, 2003Co-Authors: Olivier Chuzel, Olivier PivaAbstract:Abstract Bisabolane derivatives have been synthesized from para-substituted cinnamaldehydes according to a tandem Michael–Wittig–Horner Reaction. This sequence was applied to a short access to (+/−)-ar-turmerone.
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Tandem Michael−Wittig−Horner Reaction: One-Pot Synthesis of δ-Substituted α,β-Unsaturated Carboxylic Acid Derivatives − Application to a Concise Synthesis of (Z)- and (E)-Ochtoden-1-al
European Journal of Organic Chemistry, 2000Co-Authors: Olivier Piva, Sébastien ComesseAbstract:A new tandem Michael−Wittig−Horner Reaction has been developed to produce in high yields δ-substituted α,β-unsaturated esters, amides and lactones. The Reaction has been successfully applied to a concise synthesis of (E)- and (Z)-ochtoden-1-als, components of the male sex pheromone of boll weevil from 3-methylcyclohex-2-en-1-one.
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Tandem Michaël-Wittig Horner Reaction one-pot synthesis of δ-substituted α,β-unsaturated esters
Tetrahedron Letters, 1997Co-Authors: Olivier Piva, Sébastien ComesseAbstract:Abstract A direct synthesis of δ-substituted α,β-unsaturated esters from unsubstituted al dehydes or ketones has been accomplished in high yield by a taodem 1,4-addition and Wittig-Horner Reaction. The Copper-enolate obtained after the first step was able to deprotonate the highly acidic phosphonate generating thus the two components necessary for the second coupling Reaction.
Sébastien Comesse - One of the best experts on this subject based on the ideXlab platform.
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Tandem Michael−Wittig−Horner Reaction: One-Pot Synthesis of δ-Substituted α,β-Unsaturated Carboxylic Acid Derivatives − Application to a Concise Synthesis of (Z)- and (E)-Ochtoden-1-al
European Journal of Organic Chemistry, 2000Co-Authors: Olivier Piva, Sébastien ComesseAbstract:A new tandem Michael−Wittig−Horner Reaction has been developed to produce in high yields δ-substituted α,β-unsaturated esters, amides and lactones. The Reaction has been successfully applied to a concise synthesis of (E)- and (Z)-ochtoden-1-als, components of the male sex pheromone of boll weevil from 3-methylcyclohex-2-en-1-one.
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Tandem Michaël-Wittig Horner Reaction one-pot synthesis of δ-substituted α,β-unsaturated esters
Tetrahedron Letters, 1997Co-Authors: Olivier Piva, Sébastien ComesseAbstract:Abstract A direct synthesis of δ-substituted α,β-unsaturated esters from unsubstituted al dehydes or ketones has been accomplished in high yield by a taodem 1,4-addition and Wittig-Horner Reaction. The Copper-enolate obtained after the first step was able to deprotonate the highly acidic phosphonate generating thus the two components necessary for the second coupling Reaction.
S Pfeiffer - One of the best experts on this subject based on the ideXlab platform.
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investigation of poly arylene vinylene s 41 synthesis of soluble dialkoxy substituted poly phenylene alkenylidene s by applying the Horner Reaction for condensation polymerization
Macromolecular Chemistry and Physics, 1999Co-Authors: S Pfeiffer, H H HorholdAbstract:Soluble poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,2-ethenylene] (MEH-PPV) and its alternating copolymer poly[2,5-dimethoxy-1,4-phenylene-1,2-ethenylene-2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,2-ethenylene] (M3EH-PPV) were successfully synthesized by condensation polymerization of substituted terephthalaldehydes with substituted xylylene bisphosphonates via the Horner Reaction. This polycondensation method was also applied to the synthesis of the analogous poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,3-butadiene-1,4-diyl] (MEH-PPB), which contains a 1,3-butadiene instead of a vinylene unit. The optical data of MEH-PPV and M3EH-PPV (solid film, abs. λ max 484 nm, em. λ max 589 nm) are consistent with those previously reported for MEH-PPV from the dehydrohalogenation route. In comparison to MEH-PPV, the longer alkenylene sequence of MEH-PPB exhibits a slight red shift in its absorption and fluorescence spectra (abs. λ max 502 nm, em. λ max 604 nm). All three polyphenylene alkenylidenes (MEH-PPV, M3EH-PPV, and MEH-PPB) are completely soluble in common solvents. They are well-defined conjugated polymers of high molecular weight (M w > 20000) and possess all-trans structure. Optical quality solid films are easily prepared from these polymers by solution processing. Blends with phenyl-substituted PPV derivatives can also be prepared in this way. This combination of properties is highly desirable for many light-emitting, nonlinear optical, and photoelectrical applications.
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Investigation of poly(arylene vinylene)s, 41. Synthesis of soluble dialkoxy‐substituted poly(phenylene alkenylidene)s by applying the Horner‐Reaction for condensation polymerization
Macromolecular Chemistry and Physics, 1999Co-Authors: S Pfeiffer, H H HorholdAbstract:Soluble poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,2-ethenylene] (MEH-PPV) and its alternating copolymer poly[2,5-dimethoxy-1,4-phenylene-1,2-ethenylene-2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,2-ethenylene] (M3EH-PPV) were successfully synthesized by condensation polymerization of substituted terephthalaldehydes with substituted xylylene bisphosphonates via the Horner Reaction. This polycondensation method was also applied to the synthesis of the analogous poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-1,3-butadiene-1,4-diyl] (MEH-PPB), which contains a 1,3-butadiene instead of a vinylene unit. The optical data of MEH-PPV and M3EH-PPV (solid film, abs. λ max 484 nm, em. λ max 589 nm) are consistent with those previously reported for MEH-PPV from the dehydrohalogenation route. In comparison to MEH-PPV, the longer alkenylene sequence of MEH-PPB exhibits a slight red shift in its absorption and fluorescence spectra (abs. λ max 502 nm, em. λ max 604 nm). All three polyphenylene alkenylidenes (MEH-PPV, M3EH-PPV, and MEH-PPB) are completely soluble in common solvents. They are well-defined conjugated polymers of high molecular weight (M w > 20000) and possess all-trans structure. Optical quality solid films are easily prepared from these polymers by solution processing. Blends with phenyl-substituted PPV derivatives can also be prepared in this way. This combination of properties is highly desirable for many light-emitting, nonlinear optical, and photoelectrical applications.
Philip J. Rosenthal - One of the best experts on this subject based on the ideXlab platform.
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dipeptide vinyl sultams synthesis via the wittig Horner Reaction and activity against papain falcipain 2 and plasmodium falciparum
Bioorganic & Medicinal Chemistry Letters, 2006Co-Authors: Cláudia A. Valente, Rita C. Guedes, Rui Moreira, Jim Iley, Jiri Gut, Philip J. RosenthalAbstract:The synthesis of phosphonate derivatives of N-phenyl- and N-benzyl-gamma- and delta-sultams, and their application in the Wittig-Horner Reaction with N-Boc-L-phenylalanine aldehyde to afford E- and Z-isomers, are described. These compounds were further processed to provide five dipeptide vinyl sultams, which were found to be inactive against papain at concentrations up to 50 microM. In contrast, vinyl sultams demonstrated weak activity against recombinant falcipain-2 and Plasmodium falciparum W2.
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Dipeptide vinyl sultams: Synthesis via the Wittig–Horner Reaction and activity against papain, falcipain-2 and Plasmodium falciparum
Bioorganic & medicinal chemistry letters, 2006Co-Authors: Cláudia A. Valente, Rita C. Guedes, Rui Moreira, Jim Iley, Jiri Gut, Philip J. RosenthalAbstract:The synthesis of phosphonate derivatives of N-phenyl- and N-benzyl-gamma- and delta-sultams, and their application in the Wittig-Horner Reaction with N-Boc-L-phenylalanine aldehyde to afford E- and Z-isomers, are described. These compounds were further processed to provide five dipeptide vinyl sultams, which were found to be inactive against papain at concentrations up to 50 microM. In contrast, vinyl sultams demonstrated weak activity against recombinant falcipain-2 and Plasmodium falciparum W2.