Reaction of dichloroketene and sulfene with N,N-disubstituted 6-aminomethylene-5,6,8,9-tetrahydro-7H-benzocyclohepten-7-ones. Synthesis of 5H-benzo(5,6)cyclohepta(2,1-b)pyran and 5H-benzo(5,6)cyclohepta(1,2-e)-1,2-oxathiin derivatives.

The 1,4-cycloaddition of dichloroketene to N,N-disubstituted 6-aminomethylene-5,6,8,9-tetrahydro-7H-benzocyclohepten-7-ones afforded N,N-disubstituted 4-amino-3,3-dichloro-3,4,10,11-tetrahydro-5H-benzo[5,6]cyclohepta[2,1-b]pyran-2-ones only in the case of full or partial aromatic N-substitution. The relative adducts gave N,N-disubstituted 4-amino-3-chloro-10,11-dihydro-5H-benzo[5,6]cyclohepta[2,1-b]pyran-2-ones by dehydrochlorination. The 1,4-cycloaddition with sulfene occurred readily in the case of both aliphatic and aromatic N-substitution to give N,N-disubstituted 4-amino-3,4,10,11-tetrahydro-5H-benzo[5,6]cyclohepta[1,2-e]-1,2-oxathiin-2,2-dioxides. These compounds, as well as the pyran derivatives, can be considered as linear heterocyclic analogues of the Amitriptyline ring system.