Ringschlussreaktionen von 1‐(2‐Aminophenyl)‐1‐phenyl‐äthylenen durch Kondensation mit Phosgen

Cyclization of 1‐(2‐aminophenyl)‐1‐phenyl‐ethylenes or 1‐(2‐aminophenyl)‐1‐phenyl‐propenes (II) by condensation with phosgene led to 4‐phenyl‐carbostyrils (III) or 2‐chloro‐4‐phenyl‐quinolines (IV). Similarly, thiophosgene afforded 4‐phenyl‐thiocarbostyril. Treatment of 1‐(2‐aminophenyl)‐2‐methyl‐1‐ p ‐tolyl‐propene (VII) with phosgene led to the corresponding isocyanate IX, which cyclized in the presence of aluminum chloride with loss of a methyl group to 3‐methyl‐4‐ p ‐tolyl‐carbostyril (III‐6). However, 1‐(2‐aminophenyl)‐2‐methyl‐1‐phenyl‐propene (VIII) treated with phosgene gave the isocyanate XI and 3‐phenyl‐3‐isopropenyloxindole (X). Cyclization of the isocyanate XI with aluminium chloride led simultaneously to 3‐methyl‐4‐phenyl‐carbostyril (XIV), and with migration of a methyl group to 3‐methylene‐4‐methyl‐4‐phenyl‐3. 4‐dihydro‐carbostyril (XV).