dc.contributor.advisor | Mukherjee, Santanu | |
dc.contributor.author | Ray, Bidisha | |
dc.date.accessioned | 2021-02-10T06:21:37Z | |
dc.date.available | 2021-02-10T06:21:37Z | |
dc.date.submitted | 2018 | |
dc.identifier.uri | https://etd.iisc.ac.in/handle/2005/4866 | |
dc.description.abstract | Pyrazoles and pyrazolones are a highly explored and privileged class of aza-heterocycles with a
wide range of applications, thereby rendering a recurring interest in their synthesis and
functionalization. Majority of the reactions, developed till date involve pyrazoline-5-ones as
nucleophiles. With the application of pyrazole-4,5-diones, another mode of reactivity has emerged,
wherein pyrazolones act as electrophiles. In this chapter, enantioselective aldol reaction of 3-acetyl-
2H-chromen-2-ones to pyrazole-4,5-diones has been demonstrated. Using bifunctional tertiary
amino-amide as catalyst, the products, containing an oxygen-containing quaternary stereogenic
center and two biologically important heterocyclic frameworks, were obtained in good yields with
high enantioselectivities. This is also one of the few reactions which explored the C-4
electrophilicity of pyrazolones, rather than the usually established C-4 nucleophilicity. The reaction
has a broad substrate scope and substitutions on both coumarin ring and pyrazole-4,5-diones were
generally well tolerated. | en_US |
dc.language.iso | en_US | en_US |
dc.relation.ispartofseries | ;G29717 | |
dc.rights | I grant Indian Institute of Science the right to archive and to make available my thesis or dissertation in whole or in part in all forms of media, now hereafter known. I retain all proprietary rights, such as patent rights. I also retain the right to use in future works (such as articles or books) all or part
of this thesis or dissertation | en_US |
dc.subject | coumarin ring | en_US |
dc.subject | pyrazole-4,5-diones | en_US |
dc.subject | Pyrazoles | en_US |
dc.title | Catalytic Asymmetric Direct and Vinylogous Aldol, Michael and Alkylation Reactions | en_US |
dc.type | Thesis | en_US |
dc.degree.name | PhD | en_US |
dc.degree.level | Doctoral | en_US |
dc.degree.grantor | Indian Institute of Science | en_US |
dc.degree.discipline | Faculty of Science | en_US |