Part I. Computational, theoretical and synthetic studies of the indole arynes and their reactions. Part II. Computational, theoretical, and mechanistic studies of n-vinyltrialkylammonium, n-vinylpyridinium, and n-vinyldiazonium tetrafluoroborate salts.

Part I: Since their discovery and first report by Buszek in 2007, Indole arynes have been established as an invaluable synthetic tool in the total synthesis of many complex natural products of biological and medicinal significance. Of particular interest are polyhaloindoles, which we have exploited for their synthetic versatility utilizing metal-halogen exchange and elimination to generate indole arynes. These short-lived intermediates can then be subject to a regioselective cycloaddition, cross-coupling or other reaction. This approach has been used for the successful total synthesis of benzannulated indoles, namely, the herbindole and trinkentrin series, and the construction of diverse libraries inspired by these systems. Synthesis of these natural products required different manifolds, as no single platform has yet been discovered capable of generating all three indole arynes, and the synthetic value one would bring became readily apparent. In effort to create this universal indole aryne generating platform, we embarked on a computational study, using mechanistic modelling of thermodynamic properties and relative acidities to guide our synthetic efforts. With the unique insights granted by this methodology, we have revised a new potential universal indole aryne generating platform. The intriguing regioselectivity of the indole aryne has also inspired computational studies probing the obscure nature of the aryne bond. In this work is presented new computational data describing the observed regioselectivity of the aryne’s cycloaddition with 2-substituted furans and pyrroles, as well as new insights brought about by various indole-like heterostructures. Part II: Vinyltrialkylammonium and vinylimmonium tetrafluoroborate salts are a novel class of molecule first implied by Buszek and Jung for Diels-Alder cycloadditions. These salts are synthetically valuable due to their stability, scalability, synthetic practicality and their reactivity as novel dienophiles in Diels-Alder cycloadditions, despite their added steric bulk. In this work, we investigate the structural sources of this reactivity by analyzing the relative charge densities as calculated by natural bond orbital analysis and compare them to uncharged, unreactive variants.

Name thesis:degree_name

Ph.D. (Doctor of Philosophy)

Level thesis:degree_level

Doctoral

Discipline thesis:degree_discipline

Physics (UMKC)

Grantor

University of Missouri--Kansas City

Year dc:date.issued

2024

Author dc:creator

• Rayhart, Mark Allen

Advisors dc:contributor.advisor

• Buszek, Keith R.
• Zhu, Da-Ming, 1957-

Handle dc:identifier.uri

https://hdl.handle.net/10355/105781

OAI identifier oai:identifier

oai:mospace.umsystem.edu:10355/105781