Asymmetric epoxidation of unfunctionalised alkenes catalysed by d-fructose derivatives

In this thesis we focus on the synthesis of enantiopure epoxides using D-fructose derivatives as catalysts. A practical synthesis of the previously reported Shi’s diester catalyst (4,5-Di-O-acetyl-1,2-O-isopropylidene-D-erythro--2,3-hexadiulo-2,6-pyrano-se) was developed. Synthetic aspects such as...

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Detalles Bibliográficos
Autor: Nieto Alonso, Natalia
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2013
País:España
Institución:Universitat Rovira i virgili (URV)
Repositorio:Repositori Institucional de la Universitat Rovira i Virgili
OAI Identifier:oai:urv.cat:TDX:1291
Acceso en línea:https://hdl.handle.net/20.500.11797/TDX1291
http://hdl.handle.net/10803/128208
Access Level:acceso abierto
Palabra clave:547 - Química orgànica
54 - Química
Descripción
Sumario:In this thesis we focus on the synthesis of enantiopure epoxides using D-fructose derivatives as catalysts. A practical synthesis of the previously reported Shi’s diester catalyst (4,5-Di-O-acetyl-1,2-O-isopropylidene-D-erythro--2,3-hexadiulo-2,6-pyrano-se) was developed. Synthetic aspects such as selectivity, efficiency, cost and environmental issues of the reagents were taken into account. Optimisation of the work-up allowed for the isolation of its dihydrate derivative (no described previously). The epoxidation conditions using both D-fructose derivatives (diester and its hydrate) were optimised. Both catalysts were subsequently assayed in the asymmetric epoxidation of an array of unfunctionalised alkenes obtaining high activities and enantioselectivities. Finally, labelling experiments provided a sound understanding of the stereoinduction processes.