Application of 37622-90-5, A common heterocyclic compound, 37622-90-5, name is Ethyl 4-pyrazolecarboxylate, molecular formula is C6H8N2O2, 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.
Preparation 8; Preparation of HI-ftert-butoxycarbonylt°iperidin-^yll-IH-pyrazole-Phicarboxylic acid; A mixture of ethyl 1H-pyrazole-4-carboxylate (700 mg, 5 mmol) and NaH 60% (6 mmol) was stirred under nitrogen at 00C for 1 hour in dry DMF (15 mL). ferf-Butyl 4-[(methylsulfonyl)oxy]piperidine-1-carboxylate (1.53 gr, 5.5 mmol) dissolved in 4 mL of dry DMF was added and the resulting solution was hetaed at 100C overnight . Reaction mixture was quenched with water and extracted (x3) with ethyl acetate. Collected organic phases were dried over Na2SU4, filtered and evaporated to dryness. Residue was dissolved in MeOH (20 mL) and water (5 mL) and KOH (1.12 gr, 20 mmol) was added. The resulting solution was stirred at room temperature 24 hours, then solvents removed under reduced pressure. The residue was taken-up with AcOEt and KHSO4 5% solution. Acqueous phase was extracted with EtOAc several times. Collected organic phases were dried with Na2SU4, filtered and evaporated to dryness affording 600 mg of the title compound. 1 H-NMR (400 MHz), delta (ppm, DMSO-de): 1.42 (s, 9H) 1.73 – 1.87 (m, 2H) 1.96 – 2.03 (m, 2H) 2.82 – 2.99 (m, 2H) 4.04 (d, J=12.93 Hz, 2H) 4.34 – 4.47 (m, 1H) 7.81 (s, 1H) 8.29 (s, 1H) 12.26 (br. s., 1H)
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Patent; NERVIANO MEDICAL SCIENCES S.r.l.; MENICHINCHERI, Maria; BERTRAND, Jay, Aaron; MARCHIONNI, Chiara; NESI, Marcella; ORSINI, Paolo; PANZERI, Achille; WO2010/69966; (2010); A1;,
Pyrazole – Wikipedia,
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