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Showing 1 to 20 of 41 for “"allenes"”.
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The oxymercuration of allenes
… allene and the five possible methyl-substituted allenes was carried out in methanol. The reaction is quite rapid and even quantitative if an equivalent amount of sodium carbonate is added soon after initial mixing of the reagents. Allene yields exclusively 1,3-bis-(acetoxymercuri)-2propanone. …
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Novel Strategy for the Synthesis of Allenes.
<p>Allenes are very important chemical reagents in organic synthesis. Due to their high reactivity, they have been extensively used to carry out a variety of unique and effective chemical transformations including but not limited to ionic and free radical additions and transition metal catalyzed …
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Synthesis of Allenes by Means of Cycloelimination Reactions
Made available in DSpace on 2014-12-09T17:36:26Z (GMT). No. of bitstreams: 1 7000894.pdf: 2492625 bytes, checksum: 20ddc112f6dc23e6eab31f0e4468c40e (MD5) Previous issue date: 1969
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Asymmetric Dihydroxylation and Aziridination of Allenes and Related Chemistry
… investigation of asymmetric dihydroxylation of allenes. The efficiency of kinetic resolution of racemic allenes was also investigated by using the AD reaction on both 1,3-disubstituted and trisubstituted allenes. Steric effects, electronic effects and allene substitution are also discussed. …
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The Synthesis, Absolute Configuration, and Enantiomeric Purity of Chiral Allenes
Made available in DSpace on 2014-12-13T20:10:29Z (GMT). No. of bitstreams: 1 7913390.pdf: 3033849 bytes, checksum: f43e3c5a0245f56c4d996c38d99c6981 (MD5) Previous issue date: 1978
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A Cycloeliminative Approach to the Synthesis of Optically Active Allenes
Made available in DSpace on 2014-12-10T23:01:06Z (GMT). No. of bitstreams: 1 7114971.pdf: 2874794 bytes, checksum: f7021b4b18b79da04e77d0e1d0f76941 (MD5) Previous issue date: 1970
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Synthesis of polycyclic furans via the generation and rearrangement of strained heterocyclic allenes
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1998.
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Application of ketenes and allenes in the total synthesis of diterpene quinones and indoles
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1995.
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Gold(I) and Platinum(II)-Catalyzed Hydrofunctionalization of Allenes and Alkenes with Carbon and Nitrogen Nucleophiles
… catalyzed the intermolecular hydroarylation of allenes with indoles to form (<italic>E</italic>)-allylic indoles in modest to good yield at room temperature. The protocol was effective for monosubstituted, 1,3-disubstituted, and tetrasubstituted allenes and various indoles.</p> …
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DEVELOPMENT OF METAL-CATALYZED REACTIONS OF ALLENES WITH IMINES AND THE INVESTIGATION OF BRΘNSTED ACID CATALYZED ENE REACTIONS
… (1) to study the reaction chemistry between allenes and imines, and (2) to discover new catalysis and novel substrates for the ene reaction. Reactions between allenes and imines have been mostly unexplored despite their ability to generate useful synthetic intermediates. Described herein is …
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Preparation of benzoenyne -allenes, enyne -isocyanates and enyne -carbodiimides and their applications in the synthesis of polycyclic aromatic hydrocarbons and heterocycles
… be avoided with the non-chlorinated benzoenyne-allenes, providing direct access to novel polycyclic aromatic hydrocarbons. Several indeno-fused 4,5-diarylphenanrenes were synthesized by a consecutive C2-C6 cyclization of a symmetrical benzoenyne-allene. The formal Diels-Alder reaction involving …
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Expansion of the scope of the allenic Pauson-Khand reaction to include carboxylic acids and esters
1,3,3 Trisubstituted allenes were prepared by performing an SN2' reaction of lactones. Opening of the lactone created carboxylic acids that could then be converted to esters. By varing the functionality on the lactone and the Grignard reagents, a variety of allenes could be prepared to test the …
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Organic reactions catalyzed by copper(I) hydride complexes
… CuH-Catalyzed Allylation of Imines with Terminal Allenes A chemoselective hydrometalation process enables the use of easily accessible allenes as allylmetal nucleophile surrogates in imine allylation reactions. By modulating the nitrogen-protecting group, either highly branched- or …
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Investigation of the Steric and Electronic Properties of 3-Iminophosphine Ligands in Chelated Palladium Allyl Complexes for Use in the Regioselective Hydroamination of Allenes
A series of (3-iminophosphine)allylpalladium triflate complexes varying in both steric and electronic features was isolated and characterized. The propensity of the complexes in this series to regioselectively catalyze the hydroamination of 3-methyl-1,2-butadiene with aryl amines to form solely the …
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Reaction of allene with phenyl azide
… insight into the reaction of aryl azides with allenes.
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Large-Scale Applications of Multi-Reference Methods in Chemistry and Development of a Multi-Reference Moller-Plesset Perturbation Theory Program
… to the enyne-cumulene framework like the enyne-allenes was investigated earlier and relations to the more unusual class of enyne-ketenes are analyzed. The class of enyne-ketenes (and also the enyne-allenes) show a broad spectrum of possible intermediates (diradicals, zwitterions, allenes). The …
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Coupling reactions using flow-generated diazo compounds
… the synthesis of racemic di- and trisubstituted allenes, using copper(I) catalysis. The third chapter follows with an account of creating chiral disubstituted allenes by asymmetric coupling of flow-generated, semi-stabilised aryl aldehyde-derived diazo compounds with terminal alkynes, using a …
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Myers-Inspired Selenium-Mediated Isomerization: An Efficient Generation of Contra-Thermodynamic Allenes and Alkenes with the Potential for Reductive Deamination of Primary Amines and Metal-Free Hydrogenation of Dienes
Novel methods of catalytic metal-free isomerization reactions are scarce. By combining precedents in reductive defunctionalization reactions, coupled with previous advances in selenium-catalyzed C-N bond forming reactions, we have developed a contemporary but efficient manner of reaching …
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Studies on organic electron donors and their applications in chemistry
… mechanism for ring-forming reactions of alkoxide allenes and amide allenes is reported and supports an anionic rather than a radical process.;Chapter Two highlights the ability of diketopiperazines 1-4 to promote the cross-coupling reactions of aryl halides 5-16 with benzene in the presence of …
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