Reaction equation
OS(O)(=O)=O.[NH2:6][C:7]1[CH:12]=[CH:11][C:10]([C:13]([F:16])([F:15])[F:14])=[CH:9][N:8]=1.[N+:17]([O-])([OH:19])=[O:18].[OH-].[Na+]>>[NH2:6][C:7]1[C:12]([N+:17]([O-:19])=[O:18])=[CH:11][C:10]([C:13]([F:14])([F:16])[F:15])=[CH:9][N:8]=1Participants
5
Conditions
- Temperature
- 50 °C
Procedure
To ice-water bath cooled, conc. H2SO4 (10 mL) was added 2-amino-5-trifluoromethylpyridine (1.70 g, 10.5 mmol). The resulting solution was heated to 50° C. and 69-71% HNO3 (1.7 mL, 2.6 mmol) was added dropwise over 10 min with stirring. The resulting solution was stirred at 80° C. for 46 h, then allowed to cool to room temperature, poured into ice-water (100 mL) and basified to pH 9 with 40% aq NaOH. The resulting mixture was extracted with EtOAc (5×40 mL). The EtOAc solution was dried (MgSO4), and evaporated to give 1.33 g (61%) of 50 as a yellow powder, mp 191°-3° C. 1H NMR (CDCl3), 6.140 (bs, 1H), 7.916 (bs, 1H), 8.590 (s, 1H), 8.670 (s, 1H).
Workup
- temperatureTo ice-water bath cooled
- stirringThe resulting solution was stirred at 80° C. for 46 h
- temperatureto cool to room temperature
- extractionThe resulting mixture was extracted with EtOAc (5×40 mL)
- dry with materialThe EtOAc solution was dried (MgSO4)
- customevaporated
Sources & evidence
- ORD record
- ord-14df21c5ef1e46c3b34e1458bcb34cfa
- Source dataset
- uspto-grants-1997_04
- Patent number
- US05620978
Linked notes
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