In 1970 Wynberg and co-workers reported studies directed toward the synthesis of heterotriptycenes. la-C Following the findings of Dewar2 and Brown3 that a correlation exists between paralocalization energies and Diels-Alder reactivities, they calculated the paralocalization energies for different positions of addition in the linearly fused aromatic and heteroaromatic compounds 1-6. The most reactive positions in 1-5 were those of the