| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1344024 | Tetrahedron: Asymmetry | 2012 | 6 Pages |
The highly enantioselective Friedel–Crafts reaction of indoles with trifluoropyruvate catalyzed by a C3-symmetric cinchonine-squaramide is reported. A wide variety of trifluoromethylated indole derivatives were obtained in high yields and with excellent enantioselectivities (99% and up to >99% ee). Moreover the C3 catalyst can be easily recovered and was used five times.
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(S)-3,3,3-Trifluoro-2-hydroxy-2-(3-indolyl)-propionic acid ethyl esterC13H12F3NO3[α]D20=+18.5 (c 1.35, CHCl3), 93% eeSource of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-3,3,3-Trifluoro-2-hydroxy-2-(5-fluoro-indol-3-yl)-propionic acid methyl esterC12H9F4NO3[α]D20=+12.1 (c 0.47, CHCl3), 99% eeSource of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-3,3,3-Trifluoro-2-hydroxy-2-(5-chloro-indol-3-yl)-propionic acid methyl esterC12H9ClF3NO3[α]D20=+15.5 (c 0.87, CHCl3), 96% eeSource of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-3,3,3-Trifluoro-2-hydroxy-2-(5-bromo-indol-3-yl)-propionic acid methyl esterC12H9BrF3NO3[α]D20=+1.8 (c 0.55, CHCl3), 92% eeSource of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-3,3,3-Trifluoro-2-hydroxy-2-(5-fluoro-indol-3-yl)-propionic acid ethyl esterC13H11F4NO3[α]D20=+16.5 (c 1.04, CHCl3), 92% eeSource of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-3,3,3-Trifluoro-2-hydroxy-2-(7-methyl-indol-3-yl)-propionic acid ethyl esterC14H14F3NO3[α]D20=+5.0 (c 0.54, CHCl3), 92% eeSource of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-3,3,3-Trifluoro-2-hydroxy-2-(5-bromo-3-indolyl)-propionic acid ethyl esterC13H11BrF3NO3[α]D20=+14.8 (c 1.31, CHCl3), 86% eeSource of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-3,3,3-Trifluoro-2-hydroxy-2-(3-indolyl)-propionic acid methyl esterC12H10F3NO3[α]D20=+19.5 (c 0.88, CHCl3), 90% eeSource of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-3,3,3-Trifluoro-2-hydroxy-2-(4-methylformyl-3-indolyl)-propionic acid ethyl esterC15H14F3NO5[α]D20=+15.5 (c 0.87, CHCl3), 86% eeSource of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-3,3,3-Trifluoro-2-hydroxy-2-(5-methyl formyl-indol-3-yl)-propionic acid methyl esterC14H12F3NO5[α]D20=+2.1 (c 0.33, CHCl3), 83% eeSource of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-3,3,3-Trifluoro-2-hydroxy-2-(5-chloro-indol-3-yl)-propionic acid methyl esterC13H11ClF3NO3[α]D20=+12.5 (c 0.97, CHCl3), 80% eeSource of chirality: asymmetric synthesisAbsolute configuration: (S)
(S)-3,3,3-Trifluoro-2-hydroxy-2-(7-methyl-indol-3-yl)-propionic acid methyl esterC13H112F3NO3[α]D20=+17.9 (c 0.53, CHCl3), 80% eeSource of chirality: asymmetric synthesisAbsolute configuration: (S)
