1. Ein neuer Weg zum Morphinan
2. and a short series of 2-aryl analogs were synthesized by treatment of the appropriate unsaturated amides with polyphosphoric acid: H. V. Hansen, S. Klutchko, and R. I. Meltzer, U. S. Patent 3395145 (1968).
3. Chem. Abstr., 69, 106720 (1968).
4. Synthese von Morphinanen. (2. Mitteilung)