Die Thermolyse des Phenylazids in primären Aminen; die Konstitution des Dibenzamils

Abstract

Das von L. Wolff beim Zerfall des Phenylazids in Anilin erhaltene „Dibenzamil”︁ erweist sich als ungesättigtes Amidin mit siebengliedrigem Ring (IV oder V). Auch analoge Produkte aus Phenylazid und p‐Toluidin, p‐Phenetidin, N‐Methyl‐anilin, Benzylamin oder Cyclohexylamin sowie aus p‐Tolylazid und Anilin werden beschrieben. Ihre Konstitution zeigt, daß das zerfallende Arylazid den siebengliedrigen Ring bildet und das Arylamin in die Seitenkette eingeht. Die Acylierung von IV, nicht aber die Benzolsulfonylierung, ist mit einer Rückehr in die Benzolreihe verbunden.

Infrared spectrum and UV-induced photochemistry of matrix-isolated 5-methoxy-1-phenyl-1H-tetrazole

“…4). Characteristic bands of ACHT [19,[57][58][59]] could be clearly identified in the spectra of the irradiated matrix. Particularly noticeable is the band-mark associated with the intense antisymmetric stretching vibration of the ketenimine moiety (νC C N as.)…”

Photochemistry of fluorophenyl azides in aniline

“…The nature of this ring expansion has been under debate for several years. Huisgen and Vossius [16] suggested that the first intermediate formed from the singlet phenyl nitrene 2 was the bicyclic azirine 5. However, later IR spectroscopic studies [17] on the photochemistry of matrix isolated phenyl azide gave evidence of the formation of the didehydroazepine 4.…”

Structure and Aromatic Character of Non‐benzenoid Cyclically Conjugated Systems

“…On the other hand, the investigations of Huisgen et al [55] are of greater significance in this connection. Thermolysis of phenyl azide in aniline yielded a monocyclic isomer of azepine, the cyclic amidine or azatropilidene derivative (69) [*I.…”

“…Further investigations of the fine structure and reactivity in these octet systems are necessary in order to recognize similarities to and differences from the corresponding tropylium cations. So far only several mono-, di-, and tribenzo derivatives of the three heterotropilidenes (61) to (63) have been prepared as well as some polysubstituted derivatives stabilized by additional opportunities for resonance, and various dihydro derivatives [54,55]. Only limited conclusions are permissible from the chemical and physical behavior of the benzoheterotropilidenes (65) studied by Dimroth and Freyscldag [54] concerning the properties of the hypothetical monocyclic compounds (61) to (63), because in the bicyclic derivatives (65) stabilization of the benzene moiety by its electron sextet presumably far outweighs any stabilization of the heterocyclic 7-membered ring.…”

“…Its formation is followed rapidly by a rearrangement, presumably into the tautomeric 3H-azepine (79) [61], effecting stabilization as in the preparation of Wolfs and Huisgen's azepine derivative (69) [55], although the latter compound also profits from the gain in resonance energy associated with the formation of the amidine system. On the other hand, the driving force for the transformation of the double enamine (78) with its 8 x-electrons into the azatriene system (79) should possibly be sought in the accompanying rehybridization of the nitrogen atom and its involvement in the conjugation.…”