Electric Literature of 930-36-9, 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. 930-36-9, name is 1-Methylpyrazole belongs to pyrazoles-derivatives compound, it is a common compound, a new synthetic route is introduced below.
The (1 -methyl-1 H-pyrazol-5-yl)acetic acid used in the above procedure was prepared as follows: (i) 1 -Methyl-1 H-pyrazole-5-carbaldehyde was prepared as follows (c.f. Bioorg. Med. Chem., 2001 , 9, 961-982): A solution of 1 -methyl- 1 H-pyrazole (11.0 g, 0.134 mol) in tetrahydrofuran (200 ml) was stirred at -700C under argon. n-Butyl lithium (2.5 M in hexanes, 58.8 ml, 0.147 mol) was added dropwise maintaining the internal reaction temperature below -600C. The mixture was cooled to -700C and N, N- dimethylformamide (40 ml) was added dropwise. The reaction mixture was allowed to warm to room temperature overnight. The mixture was cooled to 00C and water (200 ml) was added followed by ethyl acetate (300 ml). The organic layer was separated and the aqueous layer was re-extracted with ethyl acetate. The combined organic extracts were washed with water, brine, then dried and evaporated. The residue was purified by flash chromatography on silica gel eluting with 0-100% ethyl acetate in hexanes to afford 1 -methyl-1 H-pyrazole-5-carbaldehyde which was used in the next step.
In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 1-Methylpyrazole, other downstream synthetic routes, hurry up and to see.
Reference:
Patent; GLAXO GROUP LIMITED; WO2008/125600; (2008); A2;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics