| Chapter 1 describes quantum mechanical calculations that demonstrate that the second step of a Claisen -- Diels-Alder reaction cascade controls regioselectivity of a reaction that gives advanced intermediates for the synthesis of gambogin and 1-O-methyllateriflorone. This work has been published in Hayden, A. E.; Xu, H.; Nicolaou, K. C.; Houk, K. N. Org. Lett. 2006, 8, 2989-2992.;Chapter 2 recounts the determination of the mechanism for the reactions of isonitriles with carboxylic acids. This has been published in Jones, G. O.; Li, X.; Hayden, A. E.; Houk, K. N.; Danishefsky, S. J. Org. Lett. 2008, 10, 4093-4096.;Chapter 3 discusses computations on the dimerization of 1,3-cyclohexadiene that revealed several highly competitive concerted and stepwise reaction pathways leading to [4 + 2] and [2 + 2] cycloadducts as well as a novel [6 + 4] ene product. Chapter 3 is a version of Ess, D. H.; Hayden, A. E.; Klarner, F.-G.; Houk, K. N. J. Org. Chem. 2008, 73, 7586-7592.;Chapter 4 details a study that showed 1,4-additions to polycyclic aromatic hydrocarbons and nitrogen-containing heterocycles follow the distortion/interaction model. This work as been published in Hayden, A. E.; Houk, K. N. J. Am. Chem. Soc. 2009, 131, 4084-4089.;Chapter 5 shows that many Diels-Alder reactions with allene dienophiles occur through stepwise [2+2] cycloadditions followed by stepwise Cope rearrangements, both involving diradical intermediates.;Chapters 6 and 7 report on two collaborative studies of Diels-Alder regioselectivity. Chapter 6 discusses the reaction of vinylidenes with 1,4-quinone monoketals and acroleins, while Chapter 7 illustrates how substituents can affect the regiochemistry of Diels-Alder reactions with juglone dienophiles.;Chapter 8 describes a hemicarcerand with a disulfide unit on one of the linkers that serves as a "gate" to control the ingress and egress of guests. Molecular mechanics computations were performed to predict suitable guests as well as to estimate the energy required for these guests to enter the capsule with the gate open and closed.;Chapters 9 discusses molecular mechanics computations on a capsule held together by hydrophobic interactions that can alter the selectivities of ene reactions of singlet oxygen with cycloalkenes. |
