| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1348199 | Tetrahedron: Asymmetry | 2011 | 14 Pages |
The straightforward determination of the absolute configuration of 2-oxo-3-indolylacetic acid derivatives 5a–e, based on analysis of the 1H NMR spectra of their oxindolylacetyl-phenyloxazolidinones 6a–e, is described. The conformational preferences for two diastereomeric amides were calculated by DFT, which matched well with the experimental results, while X-ray diffraction analysis allowed us to validate the methodology. Independent absolute configuration evidence was also obtained by vibrational circular dichroism.
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(S)-3-(2-((R)-1,3-Dimethyl-2-oxoindolin-3-yl)acetyl)-4-phenyloxazolidin-2-oneC21H20N2O4ee >98% (by 1H NMR)[α]D20=+118.7 (c 0.81, CHCl3)Source of chirality: (S)-(+)-4-phenyl-2-ozaxolidinoneAbsolute configuration: (3R,14S)
(S)-3-(2-((S)-1,3-Dimethyl-2-oxoindolin-3-yl)acetyl)-4-phenyloxazolidin-2-oneC21H20N2O4ee >98% (by 1H NMR)[α]D20=+184.3 (c 1.08, CHCl3)Source of chirality: (S)-(+)-4-phenyl-2-ozaxolidinoneAbsolute configuration: (3S,14S)
(S)-3-(2-((R)-3-Benzyl-1-methyl-2-oxoindolin-3-yl)acetyl)-4-phenyloxazolidin-2-oneC27H24N2O4ee >98% (by 1H NMR)[α]D20=+138.9 (c 1.82, CHCl3)Source of chirality: (S)-(+)-4-phenyl-2-ozaxolidinoneAbsolute configuration: (3R,14S)
(S)-3-(2-((S)-3-Benzyl-1-methyl-2-oxoindolin-3-yl)acetyl)-4-phenyloxazolidin-2-oneC27H24N2O4ee >98% (by 1H NMR)[α]D20=+183.7 (c 1.26, CHCl3)Source of chirality: (S)-(+)-4-phenyl-2-ozaxolidinoneAbsolute configuration: (3S,14S)
(S)-3-(2-((R)-1,3-Bis(3-methylbut-2-enyl)-2-oxoindolin-3-yl)acetyl)-4-phenyloxazolidin-2-oneC29H32N2O4ee >98% (by 1H NMR)[α]D20=+90.0 (c 1.34, CHCl3)Source of chirality: (S)-(+)-4-phenyl-2-ozaxolidinoneAbsolute configuration: (3R,14S)
(S)-3-(2-((S)-1,3-Bis(3-methylbut-2-enyl)-2-oxoindolin-3-yl)acetyl)-4-phenyloxazolidin-2-oneC29H32N2O4ee >98% (by 1H NMR)[α]D20=+91.0 (c 1.01, CHCl3)Source of chirality: (S)-(+)-4-phenyl-2-ozaxolidinoneAbsolute configuration: (3S,14S)
(S)-3-(2-((R)-1-Benzyl-3-(3-methylbut-2-enyl)-2-oxoindolin-3-yl)acetyl)-4-phenyloxazolidin-2-oneC31H30N2O4ee >98% (by 1H NMR)[α]D20=+119.8 (c 1.09, CHCl3)Source of chirality: (S)-(+)-4-phenyl-2-ozaxolidinoneAbsolute configuration: (3R,14S)
(S)-3-(2-((S)-1-Benzyl-3-(3-methylbut-2-enyl)-2-oxoindolin-3-yl)acetyl)-4-phenyoxazolidin-2-oneC31H30N2O4ee >98% (by 1H NMR)[α]D20=+63.7 (c 1.75, CHCl3)Source of chirality: (S)-(+)-4-phenyl-2-ozaxolidinoneAbsolute configuration: (3S,14S)
(S)-3-(2-((R)-3-Methyl-2-oxo-1-phenylindolin-3-yl)acetyl)-4-phenyloxazolidin-2-oneC26H23N2O4ee >98% (by 1H NMR)[α]D20=+166.3 (c 2.0, CHCl3)Source of chirality: (S)-(+)-4-phenyl-2-ozaxolidinoneAbsolute configuration: (3R,14S)
(S)-3-(2-((S)-3-Methyl-2-oxo-1-phenylindolin-3-yl)acetyl)-4-phenyloxazolidin-2-oneC26H23N2O4ee >98% (by 1H NMR)[α]D20=+200.0 (c 2.0, CHCl3)Source of chirality: (S)-(+)-4-phenyl-2-ozaxolidinoneAbsolute configuration: (3S,14S)
