Tricyclic Systems Containing Two Cyclopropane Rings

No complete kinetic experiments have yet been described for the isomerization reactions of tricyclic systems containing two cyclopropane rings. A number of preliminary observations have been reported and some of the isomerizations noted are given below. 

While activation energies for these reactions have not yet been obtained, it is clear from the temperatures at which the isomerizations have been found to occur that they must have significantly smaller energies of activations (perhaps by as much as 10 to 15 kcal mole than those for the cis-trans isomerizations of dialkylcyclopropanes. This suggests that the two cyclopropane rings can co-operate, especially if the geometric arrangement is favourable. 

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