Synthese von Benzazepinen und ihre Umlagerung in Chinoline und Pyrrolo [2,3‐b]chinoline

Abstract

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.

Experimental and Theoretical Studies on the Rearrangement of 2‐Oxoazepane α,α‐Amino Acids into 2′‐Oxopiperidine β2,3,3‐Amino Acids: An Example of Intramolecular Catalysis

“…The latter, Int‐B1 , is similar to the intermediate proposed by Lindenmann et al. to explain the rearrangement of the 4‐carboxybenzazepines to 1,2,3,4‐tetrahidroquinolin‐2‐ones but without theoretical support 9d . Int‐A1b was also discarded as it would not allow the nucleophilic attack required for the formation of the 2′‐oxopiperidine ring.…”

Derivatives of 1-methoxy-3-trimethylsilyloxy-1,3-butadiene for Diels-Alder reactions

“…Their NMR spectra indicated them to be homogeneous. The proton at C4 is seen, in each case, as a quartet, J 7 Hz, centered at 4.62 and 4.79 ppm, respectively. In view of the good yields of Diels-Alder products obtained from these dienes, it seemed reason-Another direct route from compound 5 to an aromatic system starts with its cycloaddition at ca.…”

“…A similar result was obtained in the conversion 20 -» 22. In each case, the higher field resonance ( 2.30,7 with Hi =2.10 Hz, in the case of 21 and 2.55, 7 with Hi = 1.80 Hz, in the case of 22) is missing. In both compounds, the lower field proton ( 2.91 in each case) which remains is the one which is slightly more coupled to Hi ( 3.50 in the case of 21 and 5.00 in the case of 22) in the parent ketone.…”

“…We now turn to the reactions of 5, 6, and 7 with maleic anhydride. This study was directed toward establishing the geometry of the latter two dienes.…”

“…The same procedure as was used for the formation of 9 was followed. From 186 mg (1 mmol) of 6 and 284 mg (2 mmol) of dimethyl acetylenedicarboxylate there was obtained, without chromatography, 148 mg (66% yield) of 13: mp (Et20-CHC13) 148-150 °C; Xmax (CHC13) 3.0, 3.31, 3.38, 5.84, 6.29 µ; 5(CDC13) 2.18 (s, 3), 3.86 (s, 3), 4.00 (s, 3), 6.82 (d, J = 8 Hz, 1), 7.02 (br s, 1), 7.80 (d, J = 8 Hz, 1) ppm.…”