Condensation of o‐bromomethylphenethyl bromide with potassium salt of N‐hydroxyurethan afforded 3‐earbethoxy‐1,3,4,5‐tetrahydro‐2,3‐benzoxazepine, which was hydrolyzed to 1,3,4,5‐tetrahydro‐2,3‐benxoxazepine (III). The reaction of o‐aeetoxymethylphenethyl bromide (VIb) with potassium salt of N‐hydroxyurethan in DMF, gave a complex mixture, from which O‐[2‐(o‐acetoxymethylphenyl)(ethyl]‐N‐earbethoxyhydroxylamine (VIIa) was separated. Subsequent desacetylation to VIIb and halogenation yielded O‐[2‐(o‐bromomethylphenyl)ethyl]‐N‐carbethoxyhydroxylamine (VIIc). By treatment of VIIc with potassium hydroxide, 2‐carbethoxy‐1,2,4,5‐tetrahydro‐3,2‐benzoxazepine (X) was obtained together with small amounts of 6,15‐diearbethoxy‐5,6,8,9,14,15,17, 18‐octahy drodibe nzo[d,I]‐1,8‐dioxa‐2,9‐diazaeyclotetradec in e (XI). Hydrolysis of X with potassium hydroxide gave 1,2,4,5‐tetrahydro‐3,2‐benzoxazepine (XII).
N‐Alkyl and N‐acyl derivatives of III and XII were also prepared.