Category: 137890-05-2

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;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Adding a certain compound to certain chemical reactions, such as: 137890-05-2, name is 1-(1-Methyl-1H-pyrazol-5-yl)ethanone, belongs to pyrazoles-derivatives compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 137890-05-2, COA of Formula: C6H8N2O

Under N2, a mixture of intermediate 1 lb (1 g) and 5-acetyl-l-methylpyrazole (168mgl.35 mmol) in THF (15 mL) was stirred at rt overnight. Then, NaBH(OAc)3 (718 mg;3.4 mmol) was added portion wise. The reaction mixture was stirred at room temperature for 72h, poured into cold water, basified with K2C03 powder and extracted with EtOAc. The organic layer was dried over MgSO4, filtered and evaporated to dryness. The residue was purified by chromatography over silica gel (irregular SiOH, 12g; mobile phase:gradient from 100% DCM, 0% MeOH to 95% DCM, 5% MeOH, 0.3% NH4OH). The fractions were collected and evaporated to dryness. The residue (300 mg) was purified asecond time by reverse phase chromatography (YMC-actus Triart Cl 8 1 Ojim30*150mm; mobile phase: gradient from 65% NH4HCO3 0.2% aq, 35% ACN to 25%NH4HCO3 0.2% aq, 75% ACN). The pure fractions were collected, evaporated to drynessyielding 104 mg of compound 224.

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Reference:
Patent; JANSSEN PHARMACEUTICA NV; ANGIBAUD, Patrick, Rene; PANDE, Vineet; HERKERT, Barbara; KROSKY, Daniel, Jason; QUEROLLE, Olivier, Alexis, Georges; PILATTE, Isabelle, Noelle, Constance; PATRICK, Aaron, Nathaniel; (250 pag.)WO2018/50686; (2018); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics