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DOI: 10.1055/sos-SD-203-00526

Oriyama, T.Science of Synthesis: Stereoselective Synthesis, (20113846.

The kinetic resolution of 2-substituted indolines catalyzed by a planar-chiral catalyst derived from 4-(pyrrolidin-1-yl)pyridine proceeds smoothly to afford the corresponding chiral indolines bearing a stereocenter at the 2-position (9098% ee).[‌70‌] Enantioselective N-acylation of secondary amides using enzymes or synthetic catalysts has never been reported. However, the kinetic resolution of various racemic oxazolidin-2-ones using catalyst (+)-31 proceeds smoothly at room temperature to afford the corresponding enantiomerically enriched secondary amides 50 and tertiary amides 51 (Scheme 22).[‌71‌] Investigation into the effects of substrate structure reveals that replacement of the phenyl group (Ar1=Ph) with a 1-naphthyl group leads to increased enantioselectivity. Asymmetric acylation of geminal dimethyl substrates (R1=Me) proceeds more slowly than for unsubstituted substrates. In these cases, higher conversions are obtained on a convenient time scale by doubling the catalyst and anhydride loadings.

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