Please use this identifier to cite or link to this item:
Title: Single-electron transfer radical activations and reactions enabled by carbene organic catalysts and organic reagents
Authors: Zhang, Yuexia
Keywords: DRNTU::Science::Chemistry
Issue Date: 2017
Source: Zhang, Y. (2017). Single-electron transfer radical activations and reactions enabled by carbene organic catalysts and organic reagents. Doctoral thesis, Nanyang Technological University, Singapore.
Abstract: This thesis focuses on exploring new single-electron transfer reaction modes enabled by N- heterocyclic carbene (NHC) organocatalysts and organic reagents. It contains four parts: Chapter 1 gives brief introductions to the development of radical reactions mediated by common radical initiators, photoredox catalysis, transition metal catalysts, electronchemistry and organocatalysts. This chapter also shows the challenges in organocatalyzed single-electron transfer reactions, especially, the limitations in NHC- catalyzed single-electron transfer reactions. Chapter 2 describes a NHC-catalyzed SET process that allows for highly enantioselective entry into β-hydroxyl esters that are widely found in natural products and bioactive molecules. The mechanistic study demonstrates the generation of multiple radical intermediates in this catalytic reaction. Chapter 3 shows an unusual trimerization of enones via a formal [2+2+2] process, which is enabled by NaOtBu and NHC. This study provides a new avenue in using NaOtBu and combined NHC/NaOtBu to generate radical intermediates from enones. Chapter 4 introduces a one-pot approach to synthesis of sulfoxides from alkenes and alkynes, this process is metal-free and no over-oxidatition of sulfoxides to sulfones is observed. N-fluorobenzenesulfonimide (NFSI) is used to enable radical generation for thiol-ene/yne reaction and subsequent selective oxidation of sulfides in situ to sulfoxides.
DOI: 10.32657/10356/71412
Schools: School of Physical and Mathematical Sciences 
Fulltext Permission: open
Fulltext Availability: With Fulltext
Appears in Collections:SPMS Theses

Files in This Item:
File Description SizeFormat 
Zhang Yuexia amended thesis .pdf7.56 MBAdobe PDFThumbnail

Page view(s)

Updated on Jul 24, 2024

Download(s) 50

Updated on Jul 24, 2024

Google ScholarTM




Items in DR-NTU are protected by copyright, with all rights reserved, unless otherwise indicated.