Recent developments in fluorocyclization methodology

Thesis

This thesis has focussed on three main projects, all concerning electrophilic fluorination and fluorocyclization methodology. To begin with we considered the development of a novel fluoro-carbocyclization reaction, which combined the use of substrates of relatively low reactivity and rarely used carbon nucleophiles. Two major and common problems with electrophilic fluorination are the choice of a suitable reaction solvent and an appropriate fluorine source. These challenges were encountered and overcome to furnish a large library of cyclized products in excellent yields starting from indene and dihydronaphthalene class substrates. Our attempts to extend this methodology to an asymmetric variant using literature protocol for asymmetric fluorination were unsuccessful due to insufficient reactivity, which prompted us to investigate a new class of chiral reagents. Using the structural core of the widely used achiral reagent Selectfluor^TM, we prepared a variety of novel reagents which displayed greater fluorinating power than what is currently available in the literature. Finally, by combining the methodology for fluoro-carbocyclization with our selection of chiral reagents we were able to successfully achieve an unprecedented metal-free asymmetric fluoro-carbocyclization.

Authors: Wolstenhulme, J; Dr. Jamie Wolstenhulme

• Publication date: 2013
• DOI: 10.5287/ora-bp8agebeo
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English
• Keywords: Fluorine; Fluorocyclization; Fluorination; Organic Chemistry; Selectfluor; Electrophilic
• Subjects: Organic chemistry