Azulene-Naphthalene-Type Rearrangements in Benzaazulene and Cycloheptabindole

摘要

Flash vacuum pyrolysis (FVP) of benza azulene yields phenanthrene and 2-ethynylbiphenyl. FVP of cycloheptab indole similarly yields phenanthridine and 2-cyanobiphenyl. The reversibility of the reactions is demonstrated by FVP of 2-ethynylbiphenyl and 2-isocyanobiphenyl. All the observed reactions are in accord with the norcaradiene-vinylidene mechanism of the azulene-naphthalene rearrangement, whereas other proposed mechanisms are ruled out.