m-Chloroperbenzoic acid → 4-Acetyl-6-chloro-2,3,4,5-tetrahydro-1,4-benzothiazepine 1-oxide
Reaction equation
ClC1C=CC=C(C(OO)=[O:9])C=1.[C:12]([N:15]1[CH2:21][C:20]2[C:22]([Cl:26])=[CH:23][CH:24]=[CH:25][C:19]=2[S:18][CH2:17][CH2:16]1)(=[O:14])[CH3:13]>ClCCl>[C:12]([N:15]1[CH2:21][C:20]2[C:22]([Cl:26])=[CH:23][CH:24]=[CH:25][C:19]=2[S:18](=[O:9])[CH2:17][CH2:16]1)(=[O:14])[CH3:13]Participants
4
Procedure
A solution of 3-chloroperbenzoic acid (1.14 g) in dichloromethane (100 ml) was added dropwise with cooling from 0° C. to -2° C. to a stirred solution of 4-acetyl-6-chloro-2,3,4,5-tetrahydro-1,4-benzothiazepine (1.34 g, prepared as Example 9 above) in dichloromethane (50 ml). The reaction mixture was stirred for 15 minutes, washed with water, dried and the solvent was removed by evaporation at reduced pressure. Purification of the residue by flash chromatography using dichloromethane/ethanol (95:5) as eluent gave 4-acetyl-6-chloro-2,3,4,5-tetrahydro-1,4-benzothiazepine 1-oxide, which was recrystallised from ethyl acetate. Yield 1.15 g (m.p. 119°-121° C.).