Über die Synthese von 1,4‐Benzoxazepinen und ihre Umlagerung in Isochinoline

The syntheses of 3‐phenyl‐5‐oxo‐4, 5‐dihydro‐1,4‐benzoxazepine (2) and ‐3‐phenyl‐5‐ethoxy‐1,4‐benzoxazepine (14) are described. 2 rearranges under the influence of sodamide into the isoquinoline derivatives 4, 5 and 6 respectively; 14 is converted quantitatively into 1‐ethoxy‐3‐phenyl‐4‐hydroxy‐isoquinoline (16) in boiling methanol, even in the absence of a strong base. Possible reaction mechanisms are discussed.