In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 27258-33-9, name is 1-Methyl-1H-pyrazole-5-carbaldehyde belongs to pyrazoles-derivatives compound, it is a common compound, a new synthetic route is introduced below. Quality Control of 1-Methyl-1H-pyrazole-5-carbaldehyde
Acetic acid (0.4 mL) was added to a solution of 2-methyl-2H-pyrazole-3-carbaldehyde (0.8 g) and 5-bromopyridine-2,3-diamine (1 g) in THF (20 mL) at room temperature. The mixture was stirred overnight at room temperature. The mixture was poured into a saturated aqueous sodium hydrogen carbonate solution, and extracted with ethyl acetate. The organic layer was washed with water and a saturated brine, dried over magnesium sulfate, and then concentrated to obtain a residue. Sodium borohydride (300 mg) was added to a solution of the residue in THF (20 mL)/methanol (50 mL) at 0C, and the mixture was stirred for 1 hour. The reaction mixture was poured into a saturated aqueous ammonium chloride solution, and extracted with ethyl acetate. The organic layer was sequentially washed with water and a saturated brine, then dried over magnesium sulfate, and concentrated under reduced pressure. The residue was purified by NH silica gel column chromatography (ethyl acetate/hexane) to obtain a pale yellow solid as 5-bromo-N3-((1-methyl-1H-pyrazol-5-yl)methyl)pyridine-2,3-diamine (0.38 g). A mixture of the obtained pale yellow solid (300 mg), acetic acid (0.1 mL), DMAP (10 mg), propylphosphonic anhydride (50% in ethyl acetate solution) (0.938 mL), DIPEA (0.464 mL) and THF (10 mL) was stirred under microwave irradiation at 200C for 2 hours. The mixture was purified by NH silica gel column chromatography (methanol/ethyl acetate) to obtain the title compound (188 mg). 1H NMR (300 MHz, DMSO-d6) delta 2.55 (3H, s), 3.81 (3H, s), 5.63 (2H, s), 5.70 (1H, d, J = 1.9 Hz), 7.30 (1H, d, J = 1.9 Hz), 8.24 (1H, d, J = 2.2 Hz), 8.42 (1H, d, J = 2.2 Hz).
The synthetic route of 27258-33-9 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Takeda Pharmaceutical Company Limited; KAWAKITA Youichi; KOJIMA Takuto; NII Noriyuki; ITO Yoshiteru; SAKAUCHI Nobuki; BANNO Hiroshi; LIU Xin; ONO Koji; IMAMURA Keisuke; IMAMURA Shinichi; (165 pag.)EP3450436; (2019); A1;,
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