In 106, where 103 is fused to two benzene rings in such a way that no canonical form can be written in which both benzene rings have six electrons, the aromaticity is reduced by annellation, as shown by the fact that the molecule rapidly converts to the more stable 107, in which both benzene rings can be fully aromatic270 (this is similar to the cycloheptatriene–norcaradiene conversions discussed on p. 1664).