Abstract
The Nazarov cyclization reaction is widely used for constructing cyclopentenoids in organic synthesis. The defining feature of the Nazarov cyclization is a 4π-electrocyclization, generated from cross-conjugated divinyl ketones, providing access to structural motifs found in many natural products and marketed drugs. Advances related to this methodology, like the incorporation of heteroatoms into the π system and the use of cyclopropanes and azirines as double bond equivalents have expanded the scope of the original reaction. These advances greatly add to the synthetic utility of the Nazarov cyclization and enable the synthesis of complex molecules in a concise fashion. In this thesis, we describe our own efforts towards the aza-Nazarov and homo-aza-Nazarov cyclization of benzimidazole enones, cyclopropanones, and isoquinolinone phenone derivatives in the pursuit of complex fused polycyclic products for biological and synthetic applications. We also report the results of antifungal screenings of the Nazarov precursors i.e., enones, cyclopropanones, and phenones. Chapter 1 provides a brief literature review of the Nazarov cyclization, including the aza-Nazarov and homo-Nazarov variants. Mainly, the historical significance and early reports of the Nazarov cyclization are discussed, along with several examples and approaches utilizing the advanced aza-Nazarov and homo-Nazarov reactions. These reactions have been widely employed to obtain complex products, attesting to the importance and diversity of this methodology in organic synthesis.