Generation and Reactions of an Octacyclic Hindered Pyramidalized Alkene
Pelayo Camps1, David Lozano1, Carla Barbaraci1
1Laboratori de Química Farmacèutica (Unitat Associada al CSIC), Facultat de Farmàcia i Ciències de l'Alimentació , Institut de Biomedicina (IBUB), Universitat de Barcelona , Av. Joan XXIII 27-31 , 08028 Barcelona , Spain.
Abstract:
Octacyclo[10.6.1.01,10.03,7.04,9.08,19.011,16.013,17]nonadeca-5,8,14-triene (27), a hindered pyramidalized alkene, has been generated from a diiodide precursor. Contrary to the usual behavior of known pyramidalized alkenes, no Diels-Alder adducts were obtained from the present alkene when it was generated by different standard procedures in the presence of different dienes. However, products derived from the reduction, t-BuLi addition, condensation with the solvent, or dimerization were isolated from these reactions, depending on the conditions used to generate it. No [2 + 2] cross product among this pyramidalized alkene and tricyclo[3.3.1.03,7]non-3(7)-ene was formed when a mixture of the corresponding precursor diiodides was reacted with sodium amalgam. The analysis of selected geometrical and orbital parameters determined from quantum mechanical calculations indicates that the degree of pyramidalization of this alkene and its higher steric hindrance compared with other polycyclic pyramidalized alkenes may explain its peculiar reactivity.
More Related Videos
Related Concept Videos
Introduction to Electrophilic Addition Reactions of Alkenes
Addition and elimination...
Free-Radical Chain Reaction and Polymerization of Alkenes
Aldehydes and Ketones to Alkenes: Wittig Reaction Mechanism
The reaction begins with the nucleophilic addition between a phosphorus ylide and the carbonyl compound. Due to its carbanionic character, phosphorus ylide acts as a strong nucleophile and attacks the electrophilic carbonyl group. This generates a charge-separated dipolar intermediate called betaine. The negatively charged oxygen atom and...
Aldehydes and Ketones to Alkenes: Wittig Reaction Overview
Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction
Nomenclature of Alkenes
As per the IUPAC rules, the longest carbon chain containing the maximum number of double bonds is identified as the parent chain and is numbered such that the doubly bonded carbon atoms receive the lowest possible numbers. The location of the double bond is indicated by the number of its first carbon atom. In branched...


