M. Alajarín, A. Vidal, María-Mar Ortín
Aug 8, 2005
Citations
0
Influential Citations
18
Citations
Journal
Tetrahedron
Abstract
Abstract The thermal treatment of N -(2-propenyl)-1-naphthylamines provided the expected aza-Claisen rearranged products, 2-(2-propenyl)-1-naphthylamines and benz[ g ]indoles, these last derived from an intramolecular hydroamination reaction on those primary products. The 2-(2-propenyl)-1-naphthylamines were converted into their triphenylphosphazene derivatives, which by aza-Wittig reaction with disubstituted ketenes yielded N -[2-(2-propenyl)-1-naphthyl] ketenimines. The heating of these ketenimines in boiling toluene induced their cyclization either via an intramolecular Diels–Alder reaction, to afford dibenz[ b , h ]acridines, or via [1,5] hydrogen migration from the sp 3 carbon atom of the propenyl substituent to the central carbon atom of the ketenimine fragment, followed by a 6π electrocyclic ring closure, to give benzo[ h ]quinolines.