m-Chloroperbenzoic acid → 5-Bromo-2-[(2,6-dichlorophenyl)methanesulfinyl]-1-oxo-1lambda~5~-pyridine
Reaction equation
[Br:1][C:2]1[CH:3]=[CH:4][C:5]([S:9][CH2:10][C:11]2[C:16]([Cl:17])=[CH:15][CH:14]=[CH:13][C:12]=2[Cl:18])=[N+:6]([O-:8])[CH:7]=1.ClC1C=CC=C(C(OO)=[O:27])C=1>C(Cl)(Cl)Cl>[Br:1][C:2]1[CH:3]=[CH:4][C:5]([S:9]([CH2:10][C:11]2[C:12]([Cl:18])=[CH:13][CH:14]=[CH:15][C:16]=2[Cl:17])=[O:27])=[N+:6]([O-:8])[CH:7]=1Participants
4
Procedure
2.3 g of 5-bromo-2-(2,6-dichlorobenzylthio)pyridine-N-oxide was dissolved in 50 ml of chloroform, and a solution of 1.6 g of metachloroperbenzoic acid (content: 70%) dissolved in 30 ml of chloroform was added dropwise thereto at 5° to 10° C. over 10 minutes. The mixture was stirred at 5° to 10° C. for an additional 2 hours. The resulting mixture was washed twice with potassium carbonate solution and dried over magnesium sulfate. The chloroform was evaporated, and the residue was recrystallized from benzene to obtain 2.0 g of 5-bromo-2-(2,6-dichlorobenzylsulfinyl)pyridine-N-oxide (Compound (2)). Yield, 83%. M.P., 187.5°-188.5° C.