Synthesis and Dynamic Properties of Substituted Cyclohepta[ef]heptalene

Cycloheptale[ef]heptalene (pleiaheptalene) is the first peri-annelated [4n]-π-electron system without aromatic partial structure. One of its derivatives that has now been synthesized is the compound 1, R=Me, which has exclusively the given double bond distribution. In solution an equilibrium is established with a π-bond isomer.