Dehalogenation of 1,3-diiodotricyclo[3.3.0.03,7]octane: Generation of 1,3dehydrotricyclo[3.3.0.03,7]octane, a 2,5-methano-bridged [2.2.1]propellane

Article abstract of DOI:10.1002/chem.200600859

Compounds isolated from the reaction of (±)-1,3-diiodotricy-clo[3.3. 0.0^3,7]octane with molten sodium or tBuLi suggest the intermediate formation of (±)-1,3-dehydrotricyclo[3.3.0.0^3,7]octane. Worthy of note is the formation of stereoisomeric bi(5-methylenebicyclo[2.2.1]hept-2- ylidene) derivatives, probably by coupling of two units of (±)-1,3- dehydrotricyclo[3.3.0.0^3,7]octane of the same or different absolute configuration followed by fragmentation, processes that have been studied by theoretical calculations.