Hydrochloric Acid → 4-(Benzyloxycarbonylamino)thiochromane-7-carboxylic acid

Participants

Reaction Steps

To a mixed solution of 4-(benzyloxycarbonylamino)thiochromane-7-carboxylic acid methyl ester (3.20 g) in methanol (50 ml), tetrahydrofuran (100 ml) and water (50 ml) was added 1N aqueous sodium hydroxide solution (20 ml), and the mixture was stirred at room temperature for 5 hr. Dilute hydrochloric acid was added to the reaction mixture until the pH became 1, and the precipitated crystals were collected by filtration. The crystals were recrystallized from acetone-hexane to give the objective 4-(benzyloxycarbonylamino)thiochromane-7-carboxylic acid (2.74 g) as colorless crystals.

Provenance & Evidence