Melatonin → N-[2-(1-acetyl-5-methoxyindolin-3-yl)ethyl]acetamide

Participants

Reaction Conditions

Reaction Steps

To a solution, cooled to 0° C., of melatonin (1 mmol) in trifluoroacetic acid (2 ml) is added dropwise borane (2 eq, 1M solution in THF). The mixture is stirred for 30 min at 0° C. followed by dropwise addition of water (1.5 ml), and the medium is left stirring for 1 h at room temperature. The mixture is then brought to pH=10 using 2N potassium hydroxide solution and is then extracted with dichloromethane. The crude product is separated on a column of flash silica (25/75/5 acetone/dichloromethane/methanol) and 110 mg of N-[2-(5-methoxyindolin-3-yl)ethyl]acetamide are obtained, which product is then acetylated with acetic anhydride in pyridine to give N-[2-(1-acetyl-5-methoxyindolin-3-yl)ethyl]acetamide.

Provenance & Evidence