+44 (0)1509 263171
Please use this identifier to cite or link to this item:
|Title: ||Novel routes to and reactions of cyclopropanes|
|Authors: ||Ross, Adam|
|Issue Date: ||2014|
|Publisher: ||© Adam Ross|
|Abstract: ||An array of different cyclopropanes have been synthesised, including the structurally
simple 1-phenylcyclopropanol. These were synthesised in yields upwards of 60%,
using the well published Kulinkovich reaction. From 1-phenylcyclopropanol,
variations of the cyclopropane core structure were synthesised, creating species
ideal for palladium cross coupling reactions, such as 1-phenylcyclopropyl
methanesulfonate and 1-phenylcyclopropyl 4-methylbenzenesulfonate. These were
formed in 50 and 60% yield respectively. Once obtained these cyclopropanes were
used to perform Suzuki cross coupling reactions towards the formation of 1,1-
diphenyl cyclopropane. Unfortunately, despite various attempts, the palladium cross
coupling reactions were unsuccessful. The work did facilitate the discovery of a
novel methodology for the synthesis of tetra substituted alkenes.
Using similar methodology as that developed for the formation of 1-
phenylcyclopropanol, a McMurry reaction was able to be performed on a number of
different ketones. This reaction formed a wide array of different tetra-substituted
alkenes with yields ranging from 20-99%, depending on the nature of the starting
material. The method, involving the use of 9 equivalents of Grignard reagent and
stoichiometric amounts of titanium isopropoxide, is a unique way of making low
valent titanium in situ, as well as being homogeneous.
Methodology for the formation of vinyl cyclopropanes containing an amide moiety
has been developed, allowing a variety of different amines to be coupled to two
different cyclopropanes. Once these species were synthesised, a palladium
catalysed cyclisation, Heck reaction, carbonylation cascade was developed. This
allowed the core cyclic structure of the stemona alkaloids to be obtained in a single
reaction vessel with good yields of up to 52% depending on the amine used.
The cascade was then applied to a fully substituted cyclic natural product core.
However, the cascade reaction was unsuccessful. Efforts to alter the structure of the
starting material, to remove the potentially hindering bromine, provided no
It was established that the tetrakis(triphenylphosphine) palladium (0) catalyst used
was too encumbered for insertion in to the sterically hindered starting material, which
is likely to be causing the failure of the reaction.|
|Description: ||A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.|
|Sponsor: ||EPSRC, Novartis|
|Appears in Collections:||PhD Theses (Chemistry)|
Files associated with this item:
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.