Search results for "Lewis acid catalysis"

showing 3 items of 23 documents

Asymmetric Aldol Reaction with Polystyrene-Supported Proline-Based Catalysts

2009

chemistry.chemical_compoundHajos–Parrish–Eder–Sauer–Wiechert reactionNitroaldol reactionAldol reactionchemistryOrganocatalysisOrganocatalysis proline supported-catalysts aldol reaction proline peptidesOrganic chemistryAldol condensationSettore CHIM/06 - Chimica OrganicaPolystyreneProlineLewis acid catalysisSynfacts
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Influence of Reactant Polarity on the Course of the Inverse-Electron-Demand Diels−Alder Reaction. A DFT Study of Regio- and Stereoselectivity, Presen…

1999

The molecular mechanisms for the inverse-electron-demand Diels−Alder reactions between nitroethene and three substituted ethenes (propene, methyl vinyl ether, and dimethylvinylamine) to give the corresponding nitroso cycloadducts have been characterized with density functional theory methods using the B3LYP/6-31G* calculational level. On the basis of stability arguments and molecular orbital analysis relative rates, regioselectivity, and stereoselectivity, the presence of Lewis acid catalyst modeled by the BH3 system and the inclusion of solvent effects as a function of the nature of substituent in the dienophile fragment are analyzed and discussed. The ortho attack mode presents transition…

chemistry.chemical_compoundchemistryOrganic ChemistrySubstituentRegioselectivityStereoselectivityNitrosoMethyl vinyl etherSolvent effectsInverse electron-demand Diels–Alder reactionPhotochemistryMedicinal chemistryLewis acid catalysisThe Journal of Organic Chemistry
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ChemInform Abstract: Influence of Reactant Polarity on the Course of the Inverse-Electron-Demand Diels-Alder Reaction. A DFT Study of Regio- and Ster…

2010

The molecular mechanisms for the inverse-electron-demand Diels−Alder reactions between nitroethene and three substituted ethenes (propene, methyl vinyl ether, and dimethylvinylamine) to give the corresponding nitroso cycloadducts have been characterized with density functional theory methods using the B3LYP/6-31G* calculational level. On the basis of stability arguments and molecular orbital analysis relative rates, regioselectivity, and stereoselectivity, the presence of Lewis acid catalyst modeled by the BH3 system and the inclusion of solvent effects as a function of the nature of substituent in the dienophile fragment are analyzed and discussed. The ortho attack mode presents transition…

chemistry.chemical_compoundchemistrySubstituentRegioselectivityStereoselectivityGeneral MedicineMethyl vinyl etherNitrosoSolvent effectsInverse electron-demand Diels–Alder reactionMedicinal chemistryLewis acid catalysisChemInform
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