Chiral phosphine-catalyzed tunable cycloaddition reactions of allenoates with benzofuranone-derived olefins for a highly regio-, diastereo- and enantioselective synthesis of spiro-benzofuranones

摘要: The first regioselective catalytic asymmetric [3 + 2] cycloaddition of benzofuranone-derived olefins with allenoates and substituted has been developed in the presence (R)-SITCP, affording different functionalized 3-spirocyclopentene benzofuran-2-ones good yields high enantioselectivities under mild conditions. substrate scope also examined. outcomes for this phosphine-catalyzed reaction can be rationalized using DFT calculations.