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Blanchot, M: Regio- and Stereoselective Catalyt...
89,90 € *
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Erscheinungsdatum: 28.09.2015, Medium: Taschenbuch, Einband: Kartoniert / Broschiert, Titel: Regio- and Stereoselective Catalytic Addition of Amides to Alkynes, Titelzusatz: Synthesis of the enamide substructure in the most atom-economic and environmentally friendly way, Autor: Blanchot, Mathieu, Verlag: Südwestdeutscher Verlag für Hochschulschriften AG Co. KG, Sprache: Deutsch, Rubrik: Organische Chemie, Seiten: 228, Informationen: Paperback, Gewicht: 356 gr, Verkäufer: averdo

Anbieter: averdo
Stand: 18.01.2020
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Cycloaddition Reactions Using Greener Technique...
74,00 € *
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The Book entitled "Cycloaddition Reactions Using Greener Techniques and Applications" reports newly synthesized N-methyl & N-phenyl- -chloro nitrones from chlorohydrin and their cycloaddition reactions with different olefins, alkynes leading to the formation of regio and stereoselective cycloadducts following green chemistry methodologies. The book also reports about the synthesis of -chloro nitrone synthesized from dry distilled chloral and cycloaddition reactions leading to the formation of regio and stereoselective cycloadducts. Majority of the reactions have been carried out in water and under microwave irradiation. High yield of cycloadducts (both isoxazolidine and isoxazoline derivatives) have been reported compared with the reactions performed in conventional solvents and thereby applications of green chemistry methodology of nirone-cycloaddition reactions have been achieved. N-methyl & N-phenyl- -chloro nitrones have been also used successfully as potential oxidizing reagents for the synthesis of aldehyde and ketones with unexpected high yields and the side products of the reaction are also used as new dipolarophiles in the synthesis of spiro cycloadducts.

Anbieter: Dodax AT
Stand: 18.01.2020
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Cycloaddition Reactions Using Greener Technique...
71,90 € *
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The Book entitled "Cycloaddition Reactions Using Greener Techniques and Applications" reports newly synthesized N-methyl & N-phenyl- -chloro nitrones from chlorohydrin and their cycloaddition reactions with different olefins, alkynes leading to the formation of regio and stereoselective cycloadducts following green chemistry methodologies. The book also reports about the synthesis of -chloro nitrone synthesized from dry distilled chloral and cycloaddition reactions leading to the formation of regio and stereoselective cycloadducts. Majority of the reactions have been carried out in water and under microwave irradiation. High yield of cycloadducts (both isoxazolidine and isoxazoline derivatives) have been reported compared with the reactions performed in conventional solvents and thereby applications of green chemistry methodology of nirone-cycloaddition reactions have been achieved. N-methyl & N-phenyl- -chloro nitrones have been also used successfully as potential oxidizing reagents for the synthesis of aldehyde and ketones with unexpected high yields and the side products of the reaction are also used as new dipolarophiles in the synthesis of spiro cycloadducts.

Anbieter: Dodax
Stand: 18.01.2020
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Studies on natural C-glycoside, mayamycin and h...
77,00 € *
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A general and convergent route has been developed for the regio- and stereoselective construction of the C-5 glycosyl angucycline framework of mayamycin. The C-glycosylation of 2-naphthol, dearomatization and Hauser annulation has been the key steps. The total synthesis of the natural product by applying this methodology was restricted by the steric perturbation of the methyl substituent in the C-glycosylation step. The peri effects in the C-glycosylation of the substituted 2-naphthols were identified. The synthetic analogues show cytotoxicity against different human cancer cell lines at low micromolar concentration. A high E-stereoselective olefination of carbonyls with thiophthalides under basic conditions have been utilized for the synthesis of stilbenoids and styryl carboxylic acids. The olefination is highly atom-efficient and proceeds via the formation of episulfide intermediate followed by extrusion of elemental sulfur. This olefination, in conjunction with retro Kolbe-Schmitt reaction, allows facile synthesis of natural hydroxystilbenoids with minimal protection of phenolic-OH.

Anbieter: Dodax AT
Stand: 18.01.2020
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Studies on natural C-glycoside, mayamycin and h...
74,90 € *
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A general and convergent route has been developed for the regio- and stereoselective construction of the C-5 glycosyl angucycline framework of mayamycin. The C-glycosylation of 2-naphthol, dearomatization and Hauser annulation has been the key steps. The total synthesis of the natural product by applying this methodology was restricted by the steric perturbation of the methyl substituent in the C-glycosylation step. The peri effects in the C-glycosylation of the substituted 2-naphthols were identified. The synthetic analogues show cytotoxicity against different human cancer cell lines at low micromolar concentration. A high E-stereoselective olefination of carbonyls with thiophthalides under basic conditions have been utilized for the synthesis of stilbenoids and styryl carboxylic acids. The olefination is highly atom-efficient and proceeds via the formation of episulfide intermediate followed by extrusion of elemental sulfur. This olefination, in conjunction with retro Kolbe-Schmitt reaction, allows facile synthesis of natural hydroxystilbenoids with minimal protection of phenolic-OH.

Anbieter: Dodax
Stand: 18.01.2020
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A Brief Overview on the Synthesis of Heterocycl...
33,90 € *
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Palladium-mediated cyclization reaction has been recognized as one of the simplest and useful tool for the regio- as well as stereoselective synthesis of carbo- and heterocyclic compounds. In the multi-step synthesis of natural products Palladium-mediated C-H activation reaction is frequently used as one of the most important steps. Further heterocyclic moieties are present in natural products, pharmaceuticals, organic materials, and numerous functional molecules. Therefore, synthetic organic chemists are interested in developing new versatile and efficient syntheses of heterocycles. This book contains brief overview in the construction of heterocyclic rings in various ways under palladium-catalyzed C-H activation.

Anbieter: Dodax AT
Stand: 18.01.2020
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A Brief Overview on the Synthesis of Heterocycl...
32,90 € *
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Palladium-mediated cyclization reaction has been recognized as one of the simplest and useful tool for the regio- as well as stereoselective synthesis of carbo- and heterocyclic compounds. In the multi-step synthesis of natural products Palladium-mediated C-H activation reaction is frequently used as one of the most important steps. Further heterocyclic moieties are present in natural products, pharmaceuticals, organic materials, and numerous functional molecules. Therefore, synthetic organic chemists are interested in developing new versatile and efficient syntheses of heterocycles. This book contains brief overview in the construction of heterocyclic rings in various ways under palladium-catalyzed C-H activation.

Anbieter: Dodax
Stand: 18.01.2020
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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: 18.01.2020
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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: 18.01.2020
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