These common heterocyclic compound, 400755-44-4, name is 1-Ethylpyrazole-3-carboxylic Acid, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. Safety of 1-Ethylpyrazole-3-carboxylic Acid
A mixture of 5-(3,5-difluorobenzyl)pyridin-2-amine (0.100 g, 0.45 mmol), 1 -ethyl- 7/-/-pyrazole-3-carboxylic acid (0.053 g, 0.38 mmol), 1 -[b/s(dimethylamino)methylene]- 7/-/-1 ,2,3-triazolo[4,5-b]pyridinium 3-oxid hexafluorophosphate (0.1 73 g, 0.45 mmol) and A/,A/-diisopropylethylamine (0.147 g, 1 .14 mmol) in anhydrous A/,A/-dimethylformamide (4.00 mL) was stirred at 20 C for 2 h. The reaction solution was extracted with ethyl acetate (20 ml_ x 20). The combined organic layers were washed with water (50 mL) and brine (50 mL) were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The crude sample was dissolved in minimal A/,A/-dimethylformamide and purified via prep-HPLC (Boston C1 8 21 *250 mm 10 pm column; acetonitrile/0.01 % aqueous trifluoroacetic acid) to give A/-(5-(3,5-difluorobenzyl)pyridin-2-yl)-1 -ethyl- 7/-/-pyrazole-3-carboxamide (0.0304 g, 0.09 mmol, 23%) as a white solid. 1 H NMR (400 MHz, Dimethylsulfoxide-c/6) d 9.68 (s, 1 H), 8.32 (d, J = 1 .8 Hz, 1 H), 8.10 (d, J = 8.5 Hz, 1 H), 7.94 (s, 1 H), 7.79 (dd, J = 8.5, 2.2 Hz, 1 H), 7.13 – 6.95 (m, 3H), 6.85 (d, J = 2.3 Hz, 1 H), 4.26 (q, J = 7.3 Hz, 2H), 3.98 (s, 2H), 1 .44 (t, J = 7.3 Hz, 3H); LCMS (ESI) m/z: 343.1 [M+H]+.
The synthetic route of 1-Ethylpyrazole-3-carboxylic Acid has been constantly updated, and we look forward to future research findings.
Reference:
Patent; YUMANITY THERAPEUTICS, INC.; LE BOURDONNEC, Bertrand; LUCAS, Matthew; OZBOYA, Kerem; PANDYA, Bhaumik; TARDIFF, Daniel; TIVITMAHAISOON, Parcharee; WRONA, Iwona; (475 pag.)WO2019/183587; (2019); A1;,
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