Acid-Catalyzed Cyclization Reactions of Substituted Acetylenic Ketones: A new Approach for the Synthesis of 3-Halofurans, Flavones, and Styrylchromones
作者:Daniel Obrecht
DOI:10.1002/hlca.19890720305
日期:1989.5.3
Acetylenic acetals of type I(Scheme 1) and acetylenic ketones of type III(Scheme 1), 37 and 38(Scheme 7) are versatile synthetic precursors for the synthesis of various heterocycles by acid-catalyzed cyclization reactions. By this way, substituted 3-halofurans of type II and IV(Scheme 1) and flavones and styrylchromones (Scheme 7) can be synthesized in good-to-excellent yields. The high degree of regioselectivity