2-Bromo-5-nitrothiazole → 3-[(5-Nitrothiazol-2-yl)mercapto]-5-phenyl-1,2,4-triazole
Reaction equation
[C:1]1([C:7]2[N:8]=[N:9][C:10](=[S:12])[N:11]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.C[O-].[Na+].Br[C:17]1[S:18][C:19]([N+:22]([O-:24])=[O:23])=[CH:20][N:21]=1>CO>[N+:22]([C:19]1[S:18][C:17]([S:12][C:10]2[N:11]=[C:7]([C:1]3[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=3)[NH:8][N:9]=2)=[N:21][CH:20]=1)([O-:24])=[O:23]Participants
Procedure
The key starting material 2-bromo-5-nitrothiazole was prepared by treating 2-amino-5-nitrothiazole (Aldrich) with sodium nitrite and hydrogen bromide (Fr. Demande 2,015,434, 1970). 3-Phenyl-1,2,4-triazole-5-thione (E. Hogarth, J. Chem. Soc. (1949) 1163) was prepared by first reacting benzoyl chloride with thiosemicarbazide in pyridine at 0° C. to give benzoyl thiosemicarbazide. Benzoyl thiosemicarbazide was treated with potassium hydroxide in ethanol to give 3-phenyl-1,2,4-triazole-5-thione. 3-Phenyl-1,2,4-triazole-5-thione (1.77 g) was then dissolved in 50 mL of methanol and treated with 0.57 g of 95% sodium methoxide, and then with 2-bromo-5-nitrothiazole (2.09 g). The mixture was stirred at room temperature for 2 hours and the precipitated sodium bromide was removed by filtration. The methanol was evaporated and the product crystallized from ethanol and water to give 1.5 g of 3-[(5-nitrothiazol-2-yl)mercapto]-5-phenyl-1,2,4-triazole, an orange solid.
Workup
- customthe precipitated sodium bromide was removed by filtration
- customThe methanol was evaporated
- customthe product crystallized from ethanol and water
Sources & evidence
- ORD record
- ord-173962dfe44e4c0da4b8cc0d56bfbcc7
- Source dataset
- uspto-grants-2000_11
- Patent number
- US06143765
Reaction notes
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