Indole-3-Butyric Acid → 4-(2-oxo-2,3-dihydro-1H-indol-3-yl)butanoic acid
Reaktionsgleichung
[NH:1]1[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[C:3]([CH2:10][CH2:11][CH2:12][C:13]([OH:15])=[O:14])=[CH:2]1.CS(C)=[O:18].Cl.[N+](=C)=[N-]>>[O:18]=[C:2]1[CH:3]([CH2:10][CH2:11][CH2:12][C:13]([OH:15])=[O:14])[C:4]2[C:9](=[CH:8][CH:7]=[CH:6][CH:5]=2)[NH:1]1Komponenten
4
Versuchsvorschrift
Similar treatment of methyl 3-(3-indolinyl)propanoic [II: R1 =R3 =H, R2 =(CH2)2COOH] (0.93 g) with DMSO/HCl, followed by esterification with diazomethane and chromatography on silica gel, gave methyl 3-(2-oxo-3-indolyl)propanoate [III: R1 -R3 =H, R2 =(CH2)2COOMe] (0.89 g, 89%) as a yellow oil (Julian P. L., Printy H. C., J. Am. Chem. Soc. 1953;75:5301-5305 report mp 79°-80° C.).