Interaction between Exocyclic s-cis Butadiene and Homoconjugated Functions. Preparation and Diels-Alder Reactivity of Remotely Substituted 2,3-Dimethylidenebicyclooctanes

Article abstract of DOI:10.1002/hlca.19820650117

The preparations of 5,6-dimethylidene-2-exo-bicyclo<2.2.2>octanol (8), its endo isomer 9, 5,6-dimethylidene-2-bicyclo<2.2.2>octanone (10) and 2exo,3exo-epoxy-5,6-dimethylidenebicyclo<2.2.2>octane (11) are described.The kinetics of their cycloaddition to tetracianoethylene has been measured in toluene at 25 deg C together with those of 2,3-dimethylidenebicyclo<2.2.2>octane (7) and 5,6-dimethylidenebicyclo<2.2.2>oct-2-ene (12).The effects of remote substituon on the Diels-Alder reactivity of 2,3-dimethylidenebicyclo<2.2.2>octanes are compared with those observed in the 2,3-dimethyl idenenorbornane series (1-6).