ETUDE DE LA REACTIVITE DE L'ION AZTURE VIS A VIS DE CATIONS HETEROCYCLIQUES-III REARRANGEMENTS THERMIQUES ET PHOTOCHIMIQUES DES AZIDES COVALENTS RESULTANT DE L'ION AZOTURE SUR DES CATIONS PYRYLIUM ET THIOPYRYLIUM DIVERSEMENT SUBSTITUES. NOUVEL ACCES A DES HETEROAZEPINES

Article abstract of DOI:10.1016/S0040-4020(01)91508-X

Azidopyrans rearrange at room temperature to 1,3-oxazepins but azidothiopyrans need heating to form unstable thiazepins. these intermediate thiazepins give the competitive formation of the corresponding pyridines after sulphur extrusion or of the corresponding thiophens after elimination of benzonitrile. Photochemical attempts to obtain thiazepins from azidothiopyrans were unsuccessful.