Electrophiles, historical background

The consequences of the distortion of the aromatic benzene ring by fusion to a cyclopropene, as it occurs in cycloproparenes, has been the subject of much discussion and speculation. Much of this debate concerned the question of bond fixation in strained aromatics which has a long historical background. In 1930 Mills and Nixon observed different reactivities towards electrophilic substitution of the a and positions in tetralin (251) and indane (252). This observation was... 

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