Synthesis of Dihydrophenanthridines and Oxoimidazolidines from Anilines and Ethylglyoxylate via Aza Diels–Alder Reaction of Arynes and KF-Induced Annulation

• DOI: 10.1021/acs.orglett.6b02186
• Publication Date: 2016-08-29T16:13:35Z
• Authors: R. Santhosh Reddy; Chandraiah Lagish...; Shuo Chen; I. N. Chaithanya ...; Yun He
• Keywords: Aryne; Annulation; Diels–Alder reaction

The transition-metal-free multicomponent coupling of arynes, anilines, and ethylglyoxylate, proceeding via an inverse electron-demand aza Diels–Alder cycloaddition N-arylation, has been demonstrated. This protocol allows rapid access to N-aryl dihydrophenanthridine derivatives in moderate high yields at room temperature from readily available starting materials. In addition, unprecedented fluoride induced annulation ethyl(arylimino)acetates led the formation highly functionalized oxoimidazolidine good under mild conditions.