40381-88-2Relevant academic research and scientific papers
Mild thermal route to phthalimidonitrene and its reaction with activated benzenes to give 2H- and 3H-azepines; X-ray crystal structure analysis of an isolable 2H-azepine
Jones, David W.,Thornton-Pett, Mark
, p. 809 - 816 (2007/10/02)
At 80 deg C 1a-acetyl-1-phthalimido-1a,6b-dihydrobenzofuroazirine 1 (X = Ac) transfers phthalimidonitrene to a series of traps: Me2SO, 2-methoxynaphthalene, indene, methyl methacrylate, methyl crotonate, mesityl oxide, cis- and trans-stilbene and cyclohexene.Oxidation of N-aminophthalimide with lead tetraacetate in the presence of these traps gives the same major products (ref. 2a).With 1,3-dimethoxybenzenes, the reagent 1 (X = Ac) provides 2H- and 3H-azepines e,g. 25a and 24a as the major products with N-phthalimidoanilines e.g. 18 formed to a lesser extent.On the other hand Pb(OAc)4 oxidation of N-aminophthalimide in the presence of 1,3-dimethoxybenzenes gives N-phthalimidoanilines and no detectable 2H- or 3H-azepines.Small quantities of acetic or benzoic acid present during the dissociation of 1 (X = Ac) in the presence of 1,3-dimethoxybenzenes cause marked increases in the formation of N-phthalimidoanilines compared with azepines.The unusually stable and isolable 2H-azepines 25 rearrange to 3H-azepines 24 only on heating and 5,7-dimethoxy-3-methyl-2-phthalimido-2H-azepine 25d is characterised by X-ray crystal structure analysis.
