Lewis-acid catalyzed reaction of 2-isopropenylaniline with ketones: Improved synthesis of 2,2,4-trisubstituted 1,2-dihydroquinolines
摘要:
The BF3. OEt2-mediated reaction of 2-isopropenylaniline with a variety of ketones to form 2,2,4-trisubstituted 1,2-dihydroquinolines was studied. Treatment of 2-isopropenylaniline with a number of different ketones in the presence of BF3. OEt2 in toluene at elevated temperatures afforded cleanly and in moderate to excellent yields the requisite 2,2,4-trisubstituted dihydroquinolines. Sterically hindered and/or cyclopropyl ketones failed to afford the desired products. (C) 1998 Elsevier Science Ltd. All rights reserved.