BECKMANN or SCHMIDT rearrangement of ethyl trans‐4‐oxo‐1‐phenyl‐2‐tetralincarboxylate (2) affords ethyl trans‐2,3,4,5‐tetrahydro‐2‐oxo‐5‐phenyl‐1H‐benzo [b] azepine‐4‐carboxylate (4). Mild treatment of trans‐2,3,4,5‐tetrahydro‐1‐methyl‐2‐oxo‐5‐phenyl‐1 H‐benzo‐[b] azepine‐4‐carboxylic acid (7) with thionyl chloride and pyridine in dimethylformamide and subsequent reaction with an amine yields the corresponding benzazepine‐4‐carboxamide. If he it is applied during the preparation of the acid chloride, rearrangement occurs yielding cis and trans derivatives of hydrocarbostyril.
2,3,4,5‐Tetrahydro‐1,4‐methano‐1‐methyl‐5‐phenyl‐1 H‐benzo‐[b] azepinium chloride (25) reacts with primary or secondary amines to cis‐tetrahydroquinoline derivatives.
When heated above its melting point, trans‐4,5‐dihydro‐2‐methylamino‐5‐phenyl‐3H‐benzo‐[b] azepine‐4‐carboxylic acid (29) rearranges with elimination of water to a mixture of cis‐and trans‐2,3,3a,4‐tetrahydro‐1‐methyl‐2‐oxo‐4‐phenyl‐1H‐pyrrolo [2,3‐b] quinoline (32 and 31). The reduction of 31 was investigated.
The mechanisms of the rearrangements are discussed.