Application of 4027-57-0, These common heterocyclic compound, 4027-57-0, name is Ethyl 5-methylpyrazole-3-carboxylate, 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.
Step 1 : Ethyl 1 -[5-(Aminosulfonyl)pyridin-2-yl]-5-methyl-1 H-pyrazoIe-3-carboxylate |mm-1 ); To a solution of ethyl 3-methylpyrazole-5-carboxylate {500 mg, 3.24 mmol) in S mL of anhydrousDMSO was added 6-chIoropyridine-3-sulfonamide (623 mg, 3.24 mmol, Adams; J. Amer. Chem. Soc; 1949; 71; 387-390), followed by the addition of potassium tert-butoxide (400 mg, 3.56 mmol). The mixture was heated at 1000C in microwave for half hour. HPLC analysis showed one third of the starting material was consumed. The mixture was heated at 1000C for one more hour and diluted with water (50 mL) with rapidly stirring. The resultant suspension was filtered. The white solid was washed with water and dried under vacuum to give the title compound mm-1 (0.75 g, yield 75%), which was used without further purification. NMR provided in Table.The regiochemistry was confirmed with a 2D NOESY 1H NMR experiment that displayed a relationship as depicted on the structure below:Elemental Analysis: Calcd for C12H14N4O4S: C, 46.44; H, 4.55; N, 18.05. Found: C, 46.48; H, 4.56; N, 17.96.
The synthetic route of 4027-57-0 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; PFIZER PRODUCTS INC.; WO2008/17932; (2008); A2;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics