Dimethylformamide → 5-Chloro-1-methyl-1H-pyrazole-4-carbaldehyde
反応式
[CH3:1][N:2]([CH3:5])C=O.CN1[C:11]([OH:12])=[CH:10][CH:9]=[N:8]1.P(Cl)(Cl)([Cl:15])=O>>[Cl:15][C:5]1[N:2]([CH3:1])[N:8]=[CH:9][C:10]=1[CH:11]=[O:12]参加物
4
反応条件
- 温度
- 80 °C
実験手順
N,N-Dimethyl formamide (2980 mg, 40.8 mmol) was added to 1-methyl-1H-pyrazol-5-ol (1000 mg, 10.19 mmol). Phosphorus oxychloride (7.46 ml, 81.5 mmol) was then added dropwise over 10 minutes. The reaction was then heated to 80° C. for 6 hours. The reaction was concentrated in vacuo and crude material neutralised with saturated aqueous NaHCO3 solution. The product was then extracted with ethyl acetate (2×25 ml), the combined organics were washed with brine (20 ml) dried over Na2SO4, filtered and concentrated in vacuo to give the title product as a brown oil which formed a crystalline solid upon standing (1130 mg, 77% yield). 1H NMR (400 MHz, CD3OD) 3.84-3.87 (3H s) 7.95-7.97 (1H d) 9.76-9.78 (1H d).