Generation and Reactions of Pentacyclo[4.3.0.02,4.03,8.05,7]non-4-ene

• Published in: Journal of organic chemistry 2007-04, Vol.72 (8), p.2996-3005
• Main Authors: Forman, Mark A, Moran, Caitlin, Herres, Joseph P, Stairs, Jason, Chopko, Emily, Pozzessere, Anthony, Kerrigan, Michael, Kelly, Carisa, Lowchyj, Lisa, Salandria, Kerry, Gallo, Annemarie, Loutzenhiser, Elizabeth
• Format: Article
• Language: English
• Subjects: Alicyclic compounds; Alicyclic compounds, terpenoids, prostaglandins, steroids; Alkenes - chemical synthesis; Alkenes - chemistry; Chemistry; Exact sciences and technology; Heterocyclic Compounds - chemical synthesis; Heterocyclic Compounds - chemistry; Isomerism; Models, Chemical; Models, Molecular; Molecular Structure; Organic chemistry; Organometallic Compounds - chemistry; Preparations and properties; Thermodynamics
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo0626313

The highly pyramidalized alkene, pentacyclo[4.3.0.02,4.03,8.05,7]non-4-ene (9), has been generated via treatment of 4,5-diiodopentacyclo[4.3.0.02,4.03,8.05,7]nonane (12) with n-butyllithium and tert-butyllithium. The title alkene has also been trapped as its Diels−Alder adduct with 1,3-diphenylisobenzofuran, 2,5-dimethylfuran, and spiro[2.4]hepta-4,6-diene. Products resulting from alkyllithium addition to the pyramidalized double bond of 9 have been isolated and fully characterized spectroscopically. The geometry, olefin strain energy, heat of hydrogenation, and relative HOMO/LUMO energies of 9 have been obtained by ab initio calculations at the MP2 and B3LYP levels using the 6-31G* basis set.