Abstract
Eleven fluoren-9-ols, monosubstituted at positions 2,3, or 9, have been submitted to reaction with hydrazoic acid in the presence of sulphuric acid, and the following have been obtained: 2-,3-,6-, and 7-nitro, 7-amino-, 2- and 7-methoxy-,2-,3-,7, and 9-methyl, 9-phenyl, and 9-bensylphenanthridines. The last is also obtained by the action of hydrasoic and sulphuric acids upon 9-benzylidenefluorene. The pairs of isomeric phenenthridines from the unsymmetrically substituted from the unsymmetrically substituted fluorenola have been separated and the product ratios have been determined. It is found that the ratio of 3- and 7-methoxyphenanthridines from the reaction with 2-methoxyfluoron-9-ol is the same as that from the acid catalyzed decomposition of 9-azido-2-methoxyfluorene. It is demonstrated that the above results support a reaction mechanism in which the carbonium ion derived from the fluorenol adds hydrazoic acid to form the protonated azide which undergoes intramolecular rearrangement, the case of migration of the substituted and unsubstituted rings being directly related to their especity for electron release at the migration origin. Reactions of phonanthridine 6- and 7-diazonium sulphates, and of 7-hydroxyphonanthridine are reported, and new syntheses of 2- and 3-nitrophonanthridines and 2:7-dinitrophonanthridine have been carried out. The Schmidt reaction with three unsymmetrically substituted fluorences has been investigated. The literature of the Schmidt reaction with ket ones has been surveyed critically, and a new proposal concerning the observed "geometrical effect" has been made. The Schmidt reaction with 2-p-toluoylbenzoic acid has been found to yield 6-oxo-2-p-tolyl-4:5-bone-1:3-oxazine: the mechanism of this reaction is discussed.