N[C:2]1[CH:7]=[CH:6][C:5]([S:8][C:9]2[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=2)=[CH:4][N:3]=1.[BrH:15].BrBr.N([O-])=O.[Na+].[OH-].[Na+]>O>[Br:15][C:2]1[CH:7]=[CH:6][C:5]([S:8][C:9]2[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=2)=[CH:4][N:3]=1
2-Amino-5-(phenylthio)pyridine (16.9 g., 0.1 mole) is added to 40 ml. of 48% hydrobromic acid, cooled to 10° C in an ice bath. While maintaining a temperature of 0°, the resultant hydrobromide salt is treated with 37.5 g. of bromine dropwise. The temperature is reduced and maintained at -10° while 14.0 g. of sodium nitrite in 200 ml. of water is added dropwise. After 1 hour at 0° C, the pH of the reaction mixture is adjusted to pH7 with 30% aqueous sodium hydroxide. Following the same workup as for the 2-chloro ananlogue, there is obtained 2-bromo-5-(phenylthio) pyridine.
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