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Regio- and Stereoselective Catalytic Addition o...
89,90 € *
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The enamide moiety is an important substructure often encountered in biologically active compounds and synthetic drugs. Furthermore, enamides and their derivatives are versatile synthetic intermediates for polymerization, [4+2] cycloaddition, crosscoupling, Heck-olefinination, Halogenation, enantioselective addition or asymmetric hydrogenation. Traditional syntheses of this important substrate class involve rather harsh reaction conditions such as high temperatures and/or the use of strong bases. Based on previous work on the addition of secondary amides to alkynes, a new broadly applicable protocol for the catalytic addition of N-nucleophiles such as primary amides, imides and thioamides to terminal alkynes was developed. The choice of ligands and additives determines the regiochemical outcome so that with two complementary catalyst systems, both the E-anti-Markovnikov products and the Z-anti-Markovnikov products can be synthesized highly regio- and stereoselectively.

Anbieter: Dodax
Stand: 19.01.2020
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Regio- and Stereoselective Catalytic Addition o...
92,50 € *
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The enamide moiety is an important substructure often encountered in biologically active compounds and synthetic drugs. Furthermore, enamides and their derivatives are versatile synthetic intermediates for polymerization, [4+2] cycloaddition, crosscoupling, Heck-olefinination, Halogenation, enantioselective addition or asymmetric hydrogenation. Traditional syntheses of this important substrate class involve rather harsh reaction conditions such as high temperatures and/or the use of strong bases. Based on previous work on the addition of secondary amides to alkynes, a new broadly applicable protocol for the catalytic addition of N-nucleophiles such as primary amides, imides and thioamides to terminal alkynes was developed. The choice of ligands and additives determines the regiochemical outcome so that with two complementary catalyst systems, both the E-anti-Markovnikov products and the Z-anti-Markovnikov products can be synthesized highly regio- and stereoselectively.

Anbieter: Dodax AT
Stand: 19.01.2020
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2-aroyl-3-arylaziridines, synthesis and reactions
39,90 € *
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The first part of the present review is devoted to the synthesis of 2-aroyl-3-aryl aziridines. Scientists are interested in these classes of heterocyclic compounds, first of all by their photochromic properties and high sensitivity towards UV-VIS irradiation. In addition, these compounds are interesting from the viewpoint of reactivity, chemo- and regio-selectivity, stereochemistry and many other. The last part is concerned with chemical behavior of 2-aroyl-3-aryl aziridines in numerous organic reactions including photochemical transformations, cycloadditions, rearrangements, regio- and stereo-selectivity, 1,3-diolar reaction, ring expansion, ring opening, deamination and other.

Anbieter: Dodax
Stand: 19.01.2020
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2-aroyl-3-arylaziridines, synthesis and reactions
41,10 € *
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The first part of the present review is devoted to the synthesis of 2-aroyl-3-aryl aziridines. Scientists are interested in these classes of heterocyclic compounds, first of all by their photochromic properties and high sensitivity towards UV-VIS irradiation. In addition, these compounds are interesting from the viewpoint of reactivity, chemo- and regio-selectivity, stereochemistry and many other. The last part is concerned with chemical behavior of 2-aroyl-3-aryl aziridines in numerous organic reactions including photochemical transformations, cycloadditions, rearrangements, regio- and stereo-selectivity, 1,3-diolar reaction, ring expansion, ring opening, deamination and other.

Anbieter: Dodax AT
Stand: 19.01.2020
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Homogeneous Catalysis & Main Group Reactivity: ...
82,90 € *
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The first part of this book describes the detailed mechanism of ruthenium catalyzed nucleophilic addition to terminal alkynes with the aim of understanding the key factors controlling the regio- and stereoselectivity of product formation. These types of reactions provide excellent methodologies for the synthesis of enamides and enol-esters. The main challenge of this method arises due to formation of product mixture, Markovnikov and anti-Markovnikov E- or Z- products. Control of regio- and stereoselectivity by modulating the electronic and steric environment along with solvent effect is nicely discussed in this part. The second part deals with the metal free asymmetric transformations and remarkable chemistry of main group radical species. This part also offers the reader to learn how to use modern theoretical techniques to predict the reactivity and product selectivity in terms of ground electronic structure and bonding parameters.

Anbieter: Dodax
Stand: 19.01.2020
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Homogeneous Catalysis & Main Group Reactivity: ...
85,30 € *
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The first part of this book describes the detailed mechanism of ruthenium catalyzed nucleophilic addition to terminal alkynes with the aim of understanding the key factors controlling the regio- and stereoselectivity of product formation. These types of reactions provide excellent methodologies for the synthesis of enamides and enol-esters. The main challenge of this method arises due to formation of product mixture, Markovnikov and anti-Markovnikov E- or Z- products. Control of regio- and stereoselectivity by modulating the electronic and steric environment along with solvent effect is nicely discussed in this part. The second part deals with the metal free asymmetric transformations and remarkable chemistry of main group radical species. This part also offers the reader to learn how to use modern theoretical techniques to predict the reactivity and product selectivity in terms of ground electronic structure and bonding parameters.

Anbieter: Dodax AT
Stand: 19.01.2020
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Synthesis of Heterocycles via Cycloadditions I
307,99 € *
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Heterocyclicmoleculesplayasigni?cantroleinlifeprocessesandhaveplayed a major rolein industrial developments of the last century, for instance in the ?eld of dyes, pharmaceuticals, pesticides, polymers etc. They comprise not onlysomeofthemostinterestingandbiologicallyimportantnaturalproducts like alkaloids, carbohydrates, nucleic acids, and antibiotics but include many practical drugs and a large segment of known synthetic organic compounds. Hencescientistshavedevotedagreatamountofeffortto?ndoptimalsynthetic approachesto a variety ofheterocyclic compounds. Amongthemostsuccessfulandselectivesyntheticprocessesarecycload- tionreactions,since theyinvolvesimultaneous orsequential formationoftwo ormorebondsoftenwithahighdegreeofstereoselectivityandregioselectivity. Forinstance, 1,3 dipolar cycloadditionsareelectronicallyequivalent to Diels Alder reactions and are among the most common 5-membered ring-forming systems. In addition they usually proceed with a high degree of stereo- and regio-control.It is therefore, not surprising that synthesis of many important classesofheterocycles,includingthoseofusefulbiologicallyactivemolecules, haveutilized cycloadditionsteps intheir formation.Furthermore,manyhe- rocyclesserve as intermediates in the synthesis of polyfunctional molecules. In this volume we present ?ve selected contributions by well-known - thors, each an authority in his ?eld. The ?rst chapter deals with construction ofisoxazolines(dihydroisoxazoles)via1,3-dipolarcycloadditionsofnitronates or of nitrile oxides generated from nitroalkanes. This includes inter- as well as intramolecular processes. Many of these heterocycles possess important synthetic and biological properties and are shown to lead to stereo- and - gioselectiveintroductionofmultifunctionalmoleculessuchasaminoalcohols, ?-amino acids, aldols, nitriles, and others.

Anbieter: Dodax AT
Stand: 19.01.2020
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Synthesis of Heterocycles via Cycloadditions I
299,59 € *
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Heterocyclicmoleculesplayasigni?cantroleinlifeprocessesandhaveplayed a major rolein industrial developments of the last century, for instance in the ?eld of dyes, pharmaceuticals, pesticides, polymers etc. They comprise not onlysomeofthemostinterestingandbiologicallyimportantnaturalproducts like alkaloids, carbohydrates, nucleic acids, and antibiotics but include many practical drugs and a large segment of known synthetic organic compounds. Hencescientistshavedevotedagreatamountofeffortto?ndoptimalsynthetic approachesto a variety ofheterocyclic compounds. Amongthemostsuccessfulandselectivesyntheticprocessesarecycload- tionreactions,since theyinvolvesimultaneous orsequential formationoftwo ormorebondsoftenwithahighdegreeofstereoselectivityandregioselectivity. Forinstance, 1,3 dipolar cycloadditionsareelectronicallyequivalent to Diels Alder reactions and are among the most common 5-membered ring-forming systems. In addition they usually proceed with a high degree of stereo- and regio-control.It is therefore, not surprising that synthesis of many important classesofheterocycles,includingthoseofusefulbiologicallyactivemolecules, haveutilized cycloadditionsteps intheir formation.Furthermore,manyhe- rocyclesserve as intermediates in the synthesis of polyfunctional molecules. In this volume we present ?ve selected contributions by well-known - thors, each an authority in his ?eld. The ?rst chapter deals with construction ofisoxazolines(dihydroisoxazoles)via1,3-dipolarcycloadditionsofnitronates or of nitrile oxides generated from nitroalkanes. This includes inter- as well as intramolecular processes. Many of these heterocycles possess important synthetic and biological properties and are shown to lead to stereo- and - gioselectiveintroductionofmultifunctionalmoleculessuchasaminoalcohols, ?-amino acids, aldols, nitriles, and others.

Anbieter: Dodax
Stand: 19.01.2020
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Regio- and Stereoselective Catalytic Addition o...
89,90 € *
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Regio- and Stereoselective Catalytic Addition of Amides to Alkynes ab 89.9 € als Taschenbuch: Synthesis of the enamide substructure in the most atom-economic and environmentally friendly way. Aus dem Bereich: Bücher, Wissenschaft, Chemie,

Anbieter: hugendubel
Stand: 19.01.2020
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