These common heterocyclic compound, 37687-18-6, name is 1-(1-Methyl-1h-pyrazol-4-yl)-ethanone, 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. Application In Synthesis of 1-(1-Methyl-1h-pyrazol-4-yl)-ethanone
Lithium bis(trimethylsilyl)amide (1.0 M in THF, 9.5 mL, 9.5 mmol) was added to a solution of methyl 5-bromo-l-(2-trimethylsilylethoxymethyl)-l,2,4-triazole-3-carboxylate (2.0 g, 5.9 mmol) and l -(l-methylpyrazol-4-yl)ethanone (1.20 g, 9.5 mmol) in THF (40 mL) at 0C. After, the reaction was warmed to rt and stirred for 1 h. The reaction was diluted with water and isopropyl acetate. A 5% citric acid solution was added and the aqueous layer was extracted with isopropyl acetate (4 x 100 mL). The combined organic layers were dried with sodium sulfate, concentrated and the crude residue was purified by flash column chromatography (silica, 0% to 100% isopropyl acetate – heptane) to givel -[5-bromo-l -(2-trimethylsilylethoxymethyl)-l ,2,4-triazol-3-yl]-3-(l -methylpyrazol-4- yl)propane-l,3-dione (2.40 g, 5.60 mmol, 94% yield). LCMS RT = 1.57 min, m/z = 427.9 [M + H]+.
The synthetic route of 1-(1-Methyl-1h-pyrazol-4-yl)-ethanone has been constantly updated, and we look forward to future research findings.
Reference:
Patent; F. HOFFMANN-LA ROCHE AG; GENENTECH, INC.; PATEL, Snahel; HAMILTON, Gregory; ZHAO, Guiling; CHEN, Huifen; DANIELS, Blake; STIVALA, Craig; (358 pag.)WO2019/12063; (2019); A1;,
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