Reference of 37622-90-5, These common heterocyclic compound, 37622-90-5, name is Ethyl 4-pyrazolecarboxylate, 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.
To a stirred solution of ethyl 1H-pyrazole-4-carboxylate (L, 4 g; 28.5 mmol) in tetrahydrofuran(50 ml) was added sodium hydride (1.36 g, 28.5 mmol) at 0C. The reaction mixture wasstirred for 1 h. Methyl iodide (6.07 g, 42.8 mmol) was added and the reaction was stirred for 18h at room temperature. The reaction mixture was concentrated under reduced pressure anddiluted with water. The resulting aqueous layer was extracted with ethyl acetate. The combined organic layers were washed with sodium bicarbonate, brine, dried over Na2SO4, filtered and concentrated under vacuum to afford ethyl 1-methyl-i H-pyrazole-4-carboxylate as a yellow liquid (LI; 3.5 g, 77% yield). ?H NMR (400 MHz, CDC13): 7.88 (s, 1H), 7.85 (s, 1H), 4.3110 4.25 (q,J= 7.2 Hz, 2H), 3.9 (s, 3H), 1.35-1.31 (t,J= 7.2 Hz, 3H). MS (M+i) 155.12.
Statistics shows that Ethyl 4-pyrazolecarboxylate is playing an increasingly important role. we look forward to future research findings about 37622-90-5.