Synthesis of New 2-Benzazepino[4,5-a]naphthalene Derivatives via 1,7-Electrocyclisation of Nonstabilised Azomethine Ylides

Novel 2-benzazepino[4,5-a]naphthalene derivatives were synthesised efficiently via 1,7-electrocyclisation of nonstabilised azomethine ylides derived from 1-aryl- or 1-alkenyl-naphthalene-2-carbaldehyde derivatives. In some cases, surprisingly, pyrrole derivatives were isolated. A mechanism for the formation of the pyrrole byproduct is proposed.