This thesis describes investigations directed towards developing a novel synthetic route to the natural products perophoramidine and the communesins, with particular emphasis placed on the formation of the two vicinal all-carbon quaternary centres contained in these molecules. Chapter 1 introduces perophoramidine and the communesin group of natural products and explains how they are related to the calycanthaceous alkaloids. The isolation of perophoramidine and the communesins is outlined and their biosynthesis is discussed. Specific structural features of these natural products are highlighted before established synthetic strategies are reviewed. Chapter 1 concludes by proposing a novel synthetic route for the synthesis of perophoramidine and the communesins that involves a Claisen rearrangement in the indolo[2,3-b]quinoline system as a key step. Chapter 2 describes model studies on the proposed Claisen rearrangement in an attempt to form a quaternary centre in the indolo[2,3-b]quinoline system. These initial studies did not result in the generation of the desired quaternary centre. However, a detailed understanding of the reactions that occur leads to the design of a new model substrate. Chapter 3 describes studies on the revised model system that result in the formation of the desired quaternary centre using a Claisen rearrangement. The differences between the two systems are discussed before an investigation into the scope of the rearrangement is described. Chapter 3 concludes by describing an investigation into a protecting group strategy that would by required with this synthetic route. Chapter 4 describes investigations into the formation of the second vicinal quaternary centre using a model system. The synthetic routes investigated lead to two separate methods for the formation of the desired quaternary centre. Chapter 5 describes investigations into the effect a C-10 substituent has on the Claisen rearrangement. Additionally, an asymmetric version of the Claisen rearrangement is examined. Chapter 5 culminates in the preparation of an intermediate relevant to an asymmetric synthesis of the communesins.

This is a thesis in two parts. Part A examines two potential routes towards the synthesis of the communesin family of alkaloids, as well as an overview of some of the successful synthetic routes to date. Our first proposed route involves the gold catalyzed isomerization of an o-amino aryallene to a vinyl imine and subsequent (formal) cycloaddition with an indole. This would have allowed quick access to the pentacyclic core of the communesins; however, the unexpected 5-endo-dig product was exclusively obtained in good to excellent yields. The second route involves the use of a Meerwein- Eschenmoser Claisen rearrangement. This route was successful in affording the C, D, E and F rings of the communesin alkaloids, however future work is required for completion of the synthesis. Also discussed in these sections is an alternative endgame approach involving a novel Pictet-Spangler reaction to afford the G ring, and the possibility of an asymmetric variation to the proposed route. Part B examines the use of alkyl aluminum sesquichlorides in the catalysis of Diels-Alder cycloadditions of sterically hindered systems, a current obstacle in organic chemistry. Previously developed methods are discussed and preliminary results are presented. Ethyl aluminum sesquichloride is compared to other alkyl aluminum catalyst, and the effects of temperature, catalysts loading, choice of solvent, the use of additives, and the use of chiral oxazolidinones are reported and what these result can tell us about the mechanism of catalysis are discussed.

This is a thesis in two parts. Part A examines two potential routes towards the synthesis of the communesin family of alkaloids, as well as an overview of some of the successful synthetic routes to date. Our first proposed route involves the gold catalyzed isomerization of an o-amino aryallene to a vinyl imine and subsequent (formal) cycloaddition with an indole. This would have allowed quick access to the pentacyclic core of the communesins; however, the unexpected 5-endo-dig product was exclusively obtained in good to excellent yields. The second route involves the use of a Meerwein- Eschenmoser Claisen rearrangement. This route was successful in affording the C, D, E and F rings of the communesin alkaloids, however future work is required for completion of the synthesis. Also discussed in these sections is an alternative endgame approach involving a novel Pictet-Spangler reaction to afford the G ring, and the possibility of an asymmetric variation to the proposed route. Part B examines the use of alkyl aluminum sesquichlorides in the catalysis of Diels-Alder cycloadditions of sterically hindered systems, a current obstacle in organic chemistry. Previously developed methods are discussed and preliminary results are presented. Ethyl aluminum sesquichloride is compared to other alkyl aluminum catalyst, and the effects of temperature, catalysts loading, choice of solvent, the use of additives, and the use of chiral oxazolidinones are reported and what these result can tell us about the mechanism of catalysis are discussed.

This is a thesis in two parts. Part A examines two potential routes towards the synthesis of the communesin family of alkaloids, as well as an overview of some of the successful synthetic routes to date. Our first proposed route involves the gold catalyzed isomerization of an o-amino aryallene to a vinyl imine and subsequent (formal) cycloaddition with an indole. This would have allowed quick access to the pentacyclic core of the communesins; however, the unexpected 5-endo-dig product was exclusively obtained in good to excellent yields. The second route involves the use of a Meerwein- Eschenmoser Claisen rearrangement. This route was successful in affording the C, D, E and F rings of the communesin alkaloids, however future work is required for completion of the synthesis. Also discussed in these sections is an alternative endgame approach involving a novel Pictet-Spangler reaction to afford the G ring, and the possibility of an asymmetric variation to the proposed route. Part B examines the use of alkyl aluminum sesquichlorides in the catalysis of Diels-Alder cycloadditions of sterically hindered systems, a current obstacle in organic chemistry. Previously developed methods are discussed and preliminary results are presented. Ethyl aluminum sesquichloride is compared to other alkyl aluminum catalyst, and the effects of temperature, catalysts loading, choice of solvent, the use of additives, and the use of chiral oxazolidinones are reported and what these result can tell us about the mechanism of catalysis are discussed.