[NH2:1][C:2]1[N:6]([C:7]2[CH:8]=[C:9]([CH:13]=[CH:14][CH:15]=2)[C:10]([OH:12])=[O:11])[N:5]=[CH:4][C:3]=1C(O)=O.C(OCC)(=O)C.C(=O)([O-])[O-].[K+].[K+].Cl>COCCOCCOC.O>[NH2:1][C:2]1[N:6]([C:7]2[CH:8]=[C:9]([CH:13]=[CH:14][CH:15]=2)[C:10]([OH:12])=[O:11])[N:5]=[CH:4][CH:3]=1The mixture of 3-(5-amino-4-carboxypyrazol-1-yl)benzoic acid (19.4 g) in diglyme (200 ml) was heated under reflux for 6 hours. To the mixture was added a mixture of ethyl acetate and water, and adjusted to pH 9 with 20% aqueous potassium carbonate solution. The separated aqueous layer was adjusted to pH 3.5 with 6N-hydrochloric acid and the mixture was extracted with a solution of ethyl acetate and tetrahydrofuran. The extract layer was washed with brine, dried over magnesium sulfate and evaporated in vacuo to give 3-(5-aminopyrazol-1-yl)benzoic acid (7.59 g).
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