Methanol → methyl (2R)-2-amino-3-(1H-indol-3-yl)propanoate hydrochloride

Participants

Reaction Steps

D-tryptophan (100 g) was suspended in methanol (500 mL) and the suspension was added to a solution of thionyl chloride (82.14 g) in methanol (500 mL) at 25° C. to 30° C. under nitrogen atmosphere. The resultant solution was stirred at reflux for 3 to 4 hours and the reaction mixture was concentrated to a residual volume of 150 mL. To the concentrated mixture, dichloromethane (700 mL) was added and the resultant solution was cooled to 0° C. to 5° C. with continuous stirring for 0.5 hours. The solid so obtained was filtered, washed with dichloromethane (200 mL), and dried in air at 40° C. to 45° C. to afford D-tryptophan methyl ester hydrochloride.

Provenance & Evidence