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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Lewis Acid Mediated Alkylation and Diels-Alder Reactions of 2H-Azirines

Risberg, Erik January 2002 (has links)
<p>This thesis describes the use of 2H-azirines as reactivesubstrates in Lewis acid catalysed nucleophilic additions andin the Diels-Alder reaction.A number of carbon nucleophiles have been added to aseries of 2H-azirines in the presence and absence ofBF3·Et2O. 3-(2-Naphthyl)-2H-azirine has been used as amodel substrate in the enantioselective addition oforganolithium reagents to an 2H-azirine.A selection of Lewis acids has been screened for theirpossible use in the normal electron demand Diels-Alder reactionbetween 3-alkyl-, 3-aryl-, and 3- carboxyl-2H-azirines and avariety of dienes. Lewis acid activation was found to shortenreaction times and facilitate lower reaction temperatures.These cycloadditions proceeded with endo selectivity providinga single diastereoisomeric product.DFT calculations of Lewis acid activated 2H-azirineshave been carried out.</p><p><b>Keywords:</b>2H-azirines, Lewis acid activation, chiralligands, organolithium reagents, Diels-Alder reactions,DFT-calculations</p>
2

Lewis Acid Mediated Alkylation and Diels-Alder Reactions of 2H-Azirines

Risberg, Erik January 2002 (has links)
This thesis describes the use of 2H-azirines as reactivesubstrates in Lewis acid catalysed nucleophilic additions andin the Diels-Alder reaction.A number of carbon nucleophiles have been added to aseries of 2H-azirines in the presence and absence ofBF3·Et2O. 3-(2-Naphthyl)-2H-azirine has been used as amodel substrate in the enantioselective addition oforganolithium reagents to an 2H-azirine.A selection of Lewis acids has been screened for theirpossible use in the normal electron demand Diels-Alder reactionbetween 3-alkyl-, 3-aryl-, and 3- carboxyl-2H-azirines and avariety of dienes. Lewis acid activation was found to shortenreaction times and facilitate lower reaction temperatures.These cycloadditions proceeded with endo selectivity providinga single diastereoisomeric product.DFT calculations of Lewis acid activated 2H-azirineshave been carried out. Keywords:2H-azirines, Lewis acid activation, chiralligands, organolithium reagents, Diels-Alder reactions,DFT-calculations / <p>NR 20140805</p>

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