5-Phenyl-1H-pyrazole-3-carboxylic acid

3-phenyl-1H-pyrazole-5-carboxylic acid is a ring assembly and a member of pyrazoles.

To a solution of 1-3 (3.4 g, 15.9 mmol) in MeOH (40 mL) was added NaOH (140 mL, 4M). The reaction mixture was stirred at room temperature for 2 hours. The reaction mixture was concentrated under reduced pressure to remove MeOH. The aqueous phase was acidified with aqueous HCl (1 M) till pH=3 and the mixture was extracted with EtOAc, dried with anhydrous NaIntermediate 96 (320mg, 1.58mmol) was dissolved in THF/water (15mL, 1 :1), lithium hydroxide monohydrate (146mg, 3.48mmol) was added and the reaction mixture was stirred for 2h. The THF was removed in vacuo and the aqueous solution was acidified to pH 1 with 1M aq HCl. The precipitate was collected by filtration to give the title compound (232mg, 78percent) as a yellow solid. LCMS: ESIntermediate 96 (320mg, 1.S8mmol) was dissolved in THF/water (l5mL, 1:1), lithiumhydroxide monohydrate (146mg, 3.48mmol) was added and the reaction mixture wasstirred for 2h. The THF was removed in vacuo and the aqueous solution was acidified to pH 1 with 1M aq HC1. The precipitate was collected by filtration to give the title0 . + +compound (232mg, 78/o) as a yellow solid. LCMS: ES 189.0 [IVIH]Alternatively, as mentioned in the text compound 6b was obtained from compound 14 in 90percent yield when 7 equiv of sodium hydroxide was used and the reaction mixture was heated at 150 °C for 2 h.General procedure: In a Biotage tube, the relevant trifluoromethylpyrazole (1 mmol) and sodium hydroxide (0.2 g, 5 mmol) were stirred in ethanol/water 1:3 (1.2 mL). The tube was sealed and heated at 120 or 150 °C, as mentioned in the text for 1 h in a microwave oven. The resulting suspension was dissolved in water; the aqueous phase was washed with dichloromethane twice and made acidic with 2 N hydrochloric acid. This was extracted with ethyl acetate twice; the organic layer was washed with brine, dried over magnesium sulfate, and concentrated to dryness to yield the corresponding acid as described below. CAUTION: the reaction conditions used lead to the release of fluorine ions that attack the glass tubes. Never recycle the reaction tubes as their resistance toward pressure and temperature may have been weakened in a process, which is releasing sodium fluoride.To a solution of compound 29b (2.6 g, 9.1 mmol) in MeOH(30 mL) and H2O (15 mL) was added LiOHH2O (0.5 g, 20.0 mmol) and the mixture was stirred at70 °C for 8 h. The reaction mixture was evaporated and H2O (15 mL) was added, then acidified byhydrochloric acid (1 M) to pH 3. The suspension was filtered and washed by H2O (10 mL), driedat 50 C for 4 h to afford 11b as a white solid (2.1g, 89.5percent yield), m.p.: 227–229 °C, decomposition.1H-NMR: 13.39 (s, 1H), 7.83 (m, 2H), 7.41–7.45 (m, 2H), 7.31–7.35 (m, 1H), 7.18(s, 1H). HRMS(ESI)calcd. For C10H8ClN2O2+: [M + H]+ m/z: 189.0659, found: 189.0659. The 1H-NMR data were in goodagreement with those reported [26].To a solution of 1-3 (3.4 g, 15.9 mmol) in MeOH (40 mL) was added NaOH (140 mL, 4M). The reaction mixture was stirred at room temperature for 2 hours. The reaction mixture was concentrated under reduced pressure to remove MeOH. The aqueous phase was acidified with aqueous HCl (1 M) till pH=3 and the mixture was extracted with EtOAc, dried with anhydrous Na2SO4, filtered and concentrated to give the crude product. The crude product was purified by silica gel chromatography eluted to give product 1-4 (2.4 g, 80.4%). MS m/z [ESI]: 189.1 [M+1].A solution of the ester 3 (0.1 g, 0.46 mmol) in MeOH (4 mL) was treated with 4 N NaOH (4 mL) and stirred at rt for 30 min. Later methanol was removed in vacuo and adjusted to pH 2-3 with aq1 N HCl and extracted with EtOAc. The organic layer was dried over anhydrous sodium sulfate and evaporated to get acid 4.

Molecular Weight:188.18
XLogP3:1.7
Hydrogen Bond Donor Count:2
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:2
Exact Mass:188.058577502
Monoisotopic Mass:188.058577502
Topological Polar Surface Area:66
Heavy Atom Count:14
Complexity:214
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes