67931-50-4Relevant academic research and scientific papers
Intermolecular Bromine Transfer of 2-Amino-7-bromotropone Derivatives Catalyzed by Strong Acid
Wakabayashi, Hidetsugu,Ishikawa, Sumio,Okai, Harue,Nozoe, Tetsuo
, p. 2840 - 2843 (2007/10/02)
Upon heating acetic acid containing a trace of concd sulfuric acid at 120 deg C under nitrogen, 2-bromo-7-(2-hydroxyanilino)tropone (1a) gave 6-bromocycloheptabenzoxazine (2a) as the main product and cycloheptabenzoxazine, its 6,8-dibromo derivative and trace amounts of other mono, di-, and tribromo compounds.This reaction became much more complex in the presence of oxygen.A similar bromine transfer was observed for 2-bromo-7-(dimethylamino)-, 7-(2-hydroxy-5-methylanilino)-, and 7-(2-methoxyanilino)tropone although the cite of the intermolecular bromine transfer depended upon the structures of the substrates and the reaction conditions.In contrast, 2a and 2-amino-5-bromotropone derivatives were completely stable towards the strong acid.Possible reaction pathways for this bromine transfer reaction are discussed.
