Melatonin → Melatonin Impurity 3
Reaction equation
[C:1](OC(=O)C)(=[O:3])[CH3:2].[CH3:8][C:9]([NH:11][CH2:12][CH2:13][C:14]1[C:18]2[CH:19]=[C:20]([O:23][CH3:24])[CH:21]=[CH:22][C:17]=2[NH:16][CH:15]=1)=[O:10]>C1C=CC=CC=1>[CH3:24][O:23][C:20]1[CH:19]=[C:18]2[C:17](=[CH:22][CH:21]=1)[NH:16][CH:15]=[C:14]2[CH2:13][CH2:12][N:11]([C:1]([CH3:2])=[O:3])[C:9](=[O:10])[CH3:8]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
Acetic anhydride (7 ml) is added with stirring to melatonin (500 mg) dissolved in benzene (50 ml). The mixture is heated for 72 h in refluxing benzene. The solvent is evaporated off and the crude product is taken up in water and then neutralized with sodium carbonate solution (pH>8). After extraction (dichloromethane), washing (water) and drying (magnesium sulphate), the crude product is flash-chromatographed (EtOAc eluent). N-[2-(5-Methoxyindol-3-yl)ethyl]diacetamide (4) (300 mg, 50% yield) is obtained.