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

Abstract

The first phosphine-catalyzed enantioselective γ-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 γ-addition products could be converted readily to optically enriched 3-fluoro-3-allyl oxindole derivatives.