Lewis Acid-Catalyzed [3 + 2]-Cyclization of Iodonium Ylides with Azadienes: Access to Spiro[benzofuran-2,2′-furan]-3-ones
Yang Liu, Chao Pi, Yangjie Wu, Xiuling Cui
Abstract
A highly regioselective synthesis of spiro[benzofuran-2,2'-furan]-3-ones has been explored via Lewis acid-catalyzed [3 + 2] cyclization of iodonium ylides with azadienes. The acidity of the Lewis acid was significantly strengthened with strong hydrogen bond donors, thereby promoting the enolization isomerization of iodonium ylides for the subsequent cycloaddition. This reaction was compatible with a broad range of substrates under the mild reaction conditions, and efficiently delivered spiro-heterocycles with excellent stereoselectivity.
Topics & Concepts
ChemistryFuranBenzofuranIsomerizationLewis acids and basesRegioselectivityCycloadditionCatalysisStereoselectivityMedicinal chemistryOrganic chemistryOxidative Organic Chemistry ReactionsCatalytic C–H Functionalization MethodsTraditional and Medicinal Uses of Annonaceae