Hydrochloric Acid → 5-Methyl-2,3,4,5-tetrahydro-1,4-benzothiazepine

Participants

Reaction Steps

To a solution of 5-methyl-2,3-dihydro-1,4-benzothiazepine (5.92 g, 33.40 mmol) in methanol (100 mL) was added a solution of sodium borohydride (3.16 g, 83.49 mmol) in water (60 mL). After being stirred at room temperature overnight, the reaction mixture was acidified with concentrated hydrochloric acid, and then stirred at room temperature for 30 minutes. After being adjusted to pH 9 with an aqueous solution of sodium hydroxide, the resulting mixture was extracted with ethyl acetate (60 mL×3). The combined organic layers were washed by brine (100 mL), dried over anhydrous sodium sulfate, and concentrated in vacuo to afford 5.6 g of 5-methyl-2,3,4,5-tetrahydro-1,4-benzothiazepine, MS obsd. (ESI+) [(M+H)+] 180.

Provenance & Evidence