Synthesis and applications of carbohydrate scaffolds via iminium activation

• Main Author: Seah, Georgina Estelle Kim Kui
• Other Authors: Liu Xuewei
• Format: Theses and Dissertations
• Language: English
• Published: 2014
• Subjects: DRNTU::Science::Chemistry::Organic chemistry::Organic synthesis; DRNTU::Science::Chemistry::Organic chemistry::Carbohydrates
• Online Access: http://hdl.handle.net/10356/55605
• Institution: Nanyang Technological University

Carbohydrate scaffolds have been known for its vast utility in organic synthesis. In particular, C3-branched sugars have been known to be useful precursors for the synthesis of some natural products. Herein, we report a stereoselective method for the synthesis of C3-branched sugars and C3-branched aminosguars via iminium and enamine activation. 4-aminocyclopentenones, which may be found embedded in many natural products and pharmaceutical drugs. In the thesis, we report an InBr3-catalyzed Nazarov cyclization reaction for the synthesis of 4-amincyclopentenones. Mechanistic studies suggests that the reaction possibly proceeds through an ‘interrupted’ Nazarov cyclization reaction. In addition, judicious choice of solvents could lead to the formation of different products, which would be discussed in detail in this thesis.