Some common heterocyclic compound, 27258-33-9, name is 1-Methyl-1H-pyrazole-5-carbaldehyde, molecular formula is C5H6N2O, 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. category: pyrazoles-derivatives
Step 2: 3-(2-Methyl-2H-pyrazol-3-yl)-acrylonitrile (4): To a stirred solution of 2-methyl-2H-pyrazole-3-carbaldehyde 3 (3.8 g, 0.0345 mol) in toluene (50 mL) was addedcyanomethyl triphenylphosphonium chloride (12.8 g, 0.0389 mol) at room temperature. DBU (1.52 mL, 0.0099 mol) was then added dropwise and heated to reflux for 3 h. After completion of the reaction, the toluene was distilled off completely under vacuum. The resultant crude product was purified on combi flash, with the desired product eluted in 15% EtOAc:Hexane toafford the product (1.1 g, 24.01% yield) as a white solid. ?HNMR(400 MHz, CDC13) oe 7.46-7.45 (d, J 176Hz, 1H), 7.3-7.25 (m, 1H), 6.56 (s, 1H), 5.79-5.75 (d, J= 16.34Hz, 1H), 3.93 (s, 3H). LC-MS (ES, m/z): [M+Hj 134.1.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 27258-33-9, its application will become more common.
Reference:
Patent; PROTEOSTASIS THERAPEUTICS, INC.; MILLER, John; BASTOS, Cecilia, M.; MUNOZ, Benito; (155 pag.)WO2017/112853; (2017); A1;,
Pyrazole – Wikipedia,
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