A CYCLIZATION OF 2-AZA-1,2-DIHYDRO-endo-DICYCLOPENTADIENE

The (±)-6-Aza[1.0]triblattane Skeleton: Contraction beyond the Wilder–Culberson Ring System

“…In 1959 Wilder and Culberson reported the synthesis of 1-aza[1.1]­triblattane ( 1 ), which interestingly preceded the synthesis of the corresponding parent hydrocarbon skeleton, bisnorditwistane ( 2 ) (i.e., ditwistbrendane), by 15 years (Scheme ). The synthetic route to access 1 was founded on an initial [4 + 2] cycloaddition reaction involving cyclopentadiene and maleimide ( 3 ) that provided most of the skeleton .…”

Heterocyclic Vinyl Ethers. XIX. Unsymmetrical 2,4-Diarylthiophenes1

“…Neither isomer undergoes rearrangement, but the stereochemistry of the addition of halogen acids to the endo compound allows intramolecular cyclization leading to a novel tertiary amine. 8 The tertiary amine V was originally isolated upon addition of hydrobromic acid to 2-aza-1,2-dihydro-ewdo-dicyclopentadiene (III). After the publication of a brief statement of these results, it was found that the tertiary amine V can be more easily obtained in pure form by the reaction of…”

Chicita Francis Culberson (1931–2023)

“…The lichen, Cladonia grayi , was the same one with which, almost 20 years earlier (Culberson & Armaleo 1992), they had demonstrated for the first time that partial desiccation of the cultured mycobiont would induce the complete predicted biosynthetic pathway for a depsidone (grayanic acid). Chicita's legacy continues in unexpected ways: Australian chemists (Fahrenhorst-Jones et al 2022) were able to synthesize some hydrocarbons based on Chicita's doctoral work—the publications from which (e.g., Culberson & Wilder 1960; Wilder & Culberson 1959) had previously been relegated to relative obscurity.…”

“…They both graduated from Wisconsin in 1954, and then enjoyed a one-year stint at Harvard University (LaGreca 2003) before arriving at Duke University in 1955, where Chicita enrolled in a Ph.D. program in the Department of Chemistry and Bill joined the faculty of the Department of Botany. Chicita's dissertation research concerned the synthesis of bicyclic monoterpenes related to camphor (Culberson 1959). After being awarded her Ph.D. in 1959, Chicita held a two-year NSF-funded research associateship in Chemistry before joining Bill in Botany as a Senior Research Associate.…”