m-Chloroperbenzoic acid → 4-Acetyl-2,3,4,5-tetrahydro-1,4-benzothiazepine 1-oxide

Participants

Reaction Steps

To a cooled solution of 1-(2,3-dihydro-1,4-benzothiazepin-4(5H)-yl)ethanone (70 g, 0.33 mol) in dichloromethane (700 mL) was added a solution of 3-chloroperoxybenzoic acid (67 g, 0.33 mol) in dichloromethane (800 mL) dropwise at 0° C. After the addition, the reaction was stirred at the same temperature for 15 minutes. The resulting reaction mixture was washed with a saturated aqueous solution of sodium carbonate (500 mL×2) and a saturated aqueous solution of sodium sulfite (500 mL×2). The combined aqueous layers were extracted with dichloromethane (200 mL×2), dried over sodium sulfate and concentrated in vacuo. The residue was purified by flash chromatography (eluting with 1-2% methanol in dichloromethane) to afford 57 g of the desired product (yield was 77%).

Provenance & Evidence