Phenanthridine cyclization by dehydrative ring closure of acyl-o-aminobiphenyls on heating with zinc chloride at 250-300° (Pictet-Hubert), or with phosphorus oxychloride in boiling nitrobenzene (Morgan-Walls):
Pictet-Hubert Reaction; Morgan-Walls Reaction
L. P. Walls, J. Chem. Soc. 1945, 294; J. Cymerman, W. F. Short, ibid. 1949, 703; R. S. Theobald, K. Schofield, Chem. Rev. 46, 175 (1950); L. P. Walls, Heterocyclic Compounds 4, 574 (1952); J. Eisch, H. Gilman, Chem. Rev. 57, 525 (1957); N. Campbell, Chemistry of Carbon Compounds IVA, 691 (1957). Cf. Bischler Napieralski Reaction.
