Application of 137890-05-2,Some common heterocyclic compound, 137890-05-2, name is 1-(1-Methyl-1H-pyrazol-5-yl)ethanone, molecular formula is C6H8N2O, 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 74 (R)-N-((5)-2-(2,4-difluorophenyl)-4-(l -methyl- lH-pyrazol-5-yl)-4-oxobutan-2-yl)-2- methylpropane-2-sulfinamide A solution of 2.4 M n-butyllithium in hexane (1.933 mL, 4.83 mmol) was added to a solution of 1-(1 -methyl- lH-pyrazol-5-yl)ethanone (600 mg, 4.83 mmol) in THF (20 mL) maintained at -78 C under a nitrogen atmosphere. The resulting mixture was allowed to stir for 20 min at -78 C. A solution of (R,E)-N-(l-(2,4-difluorophenyl)ethylidene)-2- methylpropane-2-sulfinamide (preparation 73, 836 mg, 3.22 mmol) in THF (5 mL) was slowly added over 2 min. After 5 min, the resulting solution was warmed to between -30 and -20 C and allowed to stir for 24 h. The reaction was quenched with saturated aqueous ammonium chloride solution and extracted with EtOAc. The combined organics were washed with brine, dried over magnesium sulfate, and filtered. The filtrate was concentrated in vacuo. The crude product was purified using silica gel column chromatography (5: 1-1 : 1 hexanes/ethyl acetate, linear gradient) to afford ( ?)-N-((5)-2- (2,4-difluorophenyl)-4-(l -methyl- lH-pyrazol-5-yl)-4-oxobutan-2-yl)-2-methylpropane-2- sulfinamide (330 mg, 0.861 mmol, 27 % yield). MS (M+Na)+: 406.1.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 1-(1-Methyl-1H-pyrazol-5-yl)ethanone, its application will become more common.
Reference:
Patent; BRISTOL-MYERS SQUIBB COMPANY; WU, Yong-Jin; GUERNON, Jason M.; WO2014/98831; (2014); A1;,
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