This thesis is divided into three key chapters. Chapter 1 focuses on the metal-catalysed higher-order carbocyclisation reaction whilst Chapter 2 describes metal-catalysed ene- cycloisomerisation reactions. The final section, Chapter 3, will delineate the key features of the mechanism of each transformation through kinetic and computational analysis. Chapter 1 commences with an introduction to ['m+2+2'] carbocyclisation reactions (Section 1.1). This is segregated into the following sections: metal-catalysed ['2+2+2'] (Section 1.1.1), metal-catalysed ['3+2+2'] (Section 1.1.2) and metal-catalysed ['4+2+2'] (Section 1.1.3) carbocyclisation reactions. Each section is divided into sub-sections, which correspond to their molecularity. Each sub-section begins with the intermolecular variant ([m+2+2]), followed by semi-intermolecular reactions ([(m+2)+2] and [m+(2+2)]), and conclude with the fully intramolecular molecular reaction ([(m+2+2)]). Each sub-section is partitioned depending on the degree of saturation. For example, alkyne trimerisation (Section l. 1.1. 1.1) precedes the reaction of two alkynes with one alkene (Section 1.1.1.1.2), which in turn precedes the reaction of one alkyne with two alkenes (Section 1.1.l.l.3). Section 1.2 describes our development of a regiodivergent [(2+2)+2] carbocyclisation reaction. This highlights the optimal reaction conditions as well as the scope and generality of the reaction. A hypothesis for the observed results is also discussed. The development of a regio- and diastereoselective [(3+2)+2] carbocyclisation will be discussed in Section 1.3. The section commences with an overview of three-carbon synthons in carbocyclisation reactions (Section 1.3.1.1) and highlights a plausible rationale for the potential of alkenylidenecyclopropanes in the context of a rhodium-catalysed [(3+2)+2] carbocyclisation reaction (Section 1.3.1.2). A detailed study into the optimisation and scope of the reaction is described in Section 1.3.2 and 1.3.3, respectively, which includes a plausible mechanism which accounts for the oberserved selectivities.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:569898 |
| Date | January 2011 |
| Creators | Inglesby, Phillip Anthony |
| Publisher | University of Liverpool |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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