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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: 11.07.2020
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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 EURO Synthesis of the enamide substructure in the most atom-economic and environmentally friendly way

Anbieter: ebook.de
Stand: 11.07.2020
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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: 11.07.2020
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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: 11.07.2020
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4 + 3 Cycloaddtiton Between Isomeric Dienes And...
49,00 € *
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The primary objective of this project was the exploration of the rhodium(II) (N- dodecylbenzenesulfonyl)-prolinate (Rh2(DOSP)4) catalyzed decomposition of donor/acceptor substituted diazo compounds in the presence of a mixture of E/Z dienes. The dienes in the project are provided by the enyne metathesis between various alkynes and vinyl ethers. The reaction generally displays a slight preference for the formation of E-dienes. In this project, the intermolecular tandem cyclopropanation/Cope rearrangement reaction between vinylcarbenoids and dienes was used to synthesize cycloheptadienes asymmetrically. High levels of asymmetric induction were observed with aryl substituted vinylcarbenoids. The reaction achieves high diasteroselectivity at room temperature. With the increase of the size of the 3-substituent, a highly regio- and enantioselectivity reaction was achieved. The reaction not only discriminates the diene topology, but also differentiates the propargylic stereochemistry in an effective kinetic resolution. By combining the reaction with the intermolecular enyne metathesis, a highly stereoselective synthesis of complex cycloheptadienes can be achieved.

Anbieter: Dodax
Stand: 11.07.2020
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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: 11.07.2020
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4 + 3 Cycloaddtiton Between Isomeric Dienes and...
82,90 CHF *
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The primary objective of this project was the exploration of the rhodium(II) (N- dodecylbenzenesulfonyl)-prolinate (Rh2(DOSP)4) catalyzed decomposition of donor/acceptor substituted diazo compounds in the presence of a mixture of E/Z dienes. The dienes in the project are provided by the enyne metathesis between various alkynes and vinyl ethers. The reaction generally displays a slight preference for the formation of E-dienes. In this project, the intermolecular tandem cyclopropanation/Cope rearrangement reaction between vinylcarbenoids and dienes was used to synthesize cycloheptadienes asymmetrically. High levels of asymmetric induction were observed with aryl substituted vinylcarbenoids. The reaction achieves high diasteroselectivity at room temperature. With the increase of the size of the 3-substituent, a highly regio- and enantioselectivity reaction was achieved. The reaction not only discriminates the diene topology, but also differentiates the propargylic stereochemistry in an effective kinetic resolution. By combining the reaction with the intermolecular enyne metathesis, a highly stereoselective synthesis of complex cycloheptadienes can be achieved.

Anbieter: Orell Fuessli CH
Stand: 11.07.2020
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4 + 3 Cycloaddtiton Between Isomeric Dienes and...
44,99 € *
ggf. zzgl. Versand

The primary objective of this project was the exploration of the rhodium(II) (N- dodecylbenzenesulfonyl)-prolinate (Rh2(DOSP)4) catalyzed decomposition of donor/acceptor substituted diazo compounds in the presence of a mixture of E/Z dienes. The dienes in the project are provided by the enyne metathesis between various alkynes and vinyl ethers. The reaction generally displays a slight preference for the formation of E-dienes. In this project, the intermolecular tandem cyclopropanation/Cope rearrangement reaction between vinylcarbenoids and dienes was used to synthesize cycloheptadienes asymmetrically. High levels of asymmetric induction were observed with aryl substituted vinylcarbenoids. The reaction achieves high diasteroselectivity at room temperature. With the increase of the size of the 3-substituent, a highly regio- and enantioselectivity reaction was achieved. The reaction not only discriminates the diene topology, but also differentiates the propargylic stereochemistry in an effective kinetic resolution. By combining the reaction with the intermolecular enyne metathesis, a highly stereoselective synthesis of complex cycloheptadienes can be achieved.

Anbieter: Thalia AT
Stand: 11.07.2020
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