Enantioselective synthesis of 3-fluoro-3-allyl-oxindoles via phosphine-catalyzed asymmetric gamma-addition of 3-fluoro-oxindoles to 2,3-butadienoates

摘要

The first phosphine-catalyzed enantioselective gamma-addition of 3-fluoro-oxindoles to 2,3-butadienoates has been developed. A range of 3-fluoro-substituted oxindole substrates were employed, and oxindoles containing a 3-fluoro quaternary center were constructed in high yields and with excellent enantioselectivities. The gamma-addition products could be converted readily to optically enriched 3-fluoro-3-allyl oxindole derivatives.