Article ID Journal Published Year Pages File Type
1345334 Tetrahedron: Asymmetry 2015 5 Pages PDF
Abstract

The asymmetric synthesis of 3-alkyl-3-hydroxyindolin-2-ones via direct aldol reaction of isatin with ketones catalyzed by natural amino acid salts is described, in which the phenylalanine lithium salt was found to be the best catalyst. This strategy was then applied to a variety of isatin and ketone substrates and the corresponding aldol products were obtained in excellent yields (up to 97%) with good to excellent enantioselectivities (up to 90%).

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(S)-3-Hydroxy-3-(2-oxopropyl)indolin-2-oneC11H13NO370% ee[α]D25 = −11.0 (c 1.0, MeOH) determined by HPLCThe absolute configuration was determined by comparison of the rotation with previously reported valuesAbsolute configuration: (S)

(S)-3-Hydroxy-1-methyl-3-(2-oxopropyl)indolin-2-oneC12H13NO381% ee[α]D25 = −15.2 (c 2.4, MeOH) determined by HPLCThe absolute configuration was determined by comparison of the rotation with previously reported valuesAbsolute configuration: (S)

(S)-1-Benzyl-3-hydroxy-3-(2-oxopropyl)indolin-2-oneC18H17NO387% ee[α]D25 = −16.4 (c 2.8, MeOH) determined by HPLCThe absolute configuration was determined by comparison of the rotation with previously reported valuesAbsolute configuration: (S)

(S)-3-Hydroxy-1-(4-methoxybenzyl)-3-(2-oxopropyl)indolin-2-oneC19H19NO487% ee[α]D25 = −16.3 (c 3.7, MeOH) determined by HPLCThe absolute configuration was determined by comparison of the rotation with previously reported valuesAbsolute configuration: (S)

(S)-3-Hydroxy-5-methyl-3-(2-oxopropyl)indolin-2-oneC12H13NO366% ee[α]D25 = −13.0 (c 1.0, MeOH) determined by HPLCThe absolute configuration was determined by comparison of the rotation with previously reported valuesAbsolute configuration: (S)

(S)-5-Fluoro-3-hydroxy-3-(2-oxopropyl)indolin-2-oneC11H10FNO377% ee[α]D25 = −17.0 (c 1.0, MeOH) determined by HPLCThe absolute configuration was determined by comparison of the rotation with previously reported valuesAbsolute configuration: (S)

(S)-5-Chloro-3-hydroxy-3-(2-oxopropyl)indolin-2-oneC11H10ClNO378% ee[α]D25 = −22.0 (c 1.0, MeOH) determined by HPLCThe absolute configuration was determined by comparison of the rotation with previously reported valuesAbsolute configuration: (S)

Related Topics
Physical Sciences and Engineering Chemistry Inorganic Chemistry
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