Transannular Claisen Rearrangements of α-Sulfonyl Lactones
Author(s)
Gore, Sophie
Type
Thesis
Abstract
This thesis is divided into three sections.
Section one is a review of transannular pericyclic reactions. It covers the four main
types of pericyclic reaction and major contributions in the field to date. Recent
applications of these reactions to natural product synthesis are also included.
Section two discusses the results of research efforts into transannular Claisen
rearrangements of α-sulfonyl lactones. The background to the project is discussed
along with initial investigations into the transannular Claisen and decarboxylative
Claisen rearrangements (dCr) of the 7-membered α-tosyl lactone to form vinyl
cyclopropanes. Stereoselectivity from within the pericyclic array, by substitution at the
lactone C7 position is examined. Efforts towards stereoinduction from outside of the
pericyclic array are also detailed, along with aryl substitution at the lactone C5 position
to form highly substituted vinyl cyclopropanes. Extension of this methodology to the
unprecedented transannular Claisen rearrangement and dCr reaction of 8-membered α-
tosyl lactones to give vinyl cyclobutanes is reported. Finally, efforts towards a novel
synthetic route to (±)-grandisol utilising the transannular Claisen rearrangement
chemistry is described.
Section three details the experimental procedures and spectroscopic data for the
compounds described in section two.
Section one is a review of transannular pericyclic reactions. It covers the four main
types of pericyclic reaction and major contributions in the field to date. Recent
applications of these reactions to natural product synthesis are also included.
Section two discusses the results of research efforts into transannular Claisen
rearrangements of α-sulfonyl lactones. The background to the project is discussed
along with initial investigations into the transannular Claisen and decarboxylative
Claisen rearrangements (dCr) of the 7-membered α-tosyl lactone to form vinyl
cyclopropanes. Stereoselectivity from within the pericyclic array, by substitution at the
lactone C7 position is examined. Efforts towards stereoinduction from outside of the
pericyclic array are also detailed, along with aryl substitution at the lactone C5 position
to form highly substituted vinyl cyclopropanes. Extension of this methodology to the
unprecedented transannular Claisen rearrangement and dCr reaction of 8-membered α-
tosyl lactones to give vinyl cyclobutanes is reported. Finally, efforts towards a novel
synthetic route to (±)-grandisol utilising the transannular Claisen rearrangement
chemistry is described.
Section three details the experimental procedures and spectroscopic data for the
compounds described in section two.
Date Issued
2009-06
Date Awarded
2009-09
Copyright Statement
Attribution NoDerivatives 4.0 International Licence (CC BY-ND)
Advisor
Craig, Donald
Creator
Gore, Sophie
Publisher Department
Chemistry
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)