تفاعل #58959

معادلة التفاعل

1-methyl-1H-pyrazole-4-carbaldehyde

sodium hydride

ethyl diethylphosphonoacetate

N,N-dimethylformamide

→

ethyl (2E)-3-(1-methyl-1H-pyrazol-4-yl)acrylate

المردود 64.2%

المذيبات

water

ظروف التفاعل

المعالجة

1. 1
   استخلاصthe mixture was extracted with ethyl acetate
2. 2
   غسيلThe organic layer was washed with water
3. 3
   تجفيفdried over anhydrous magnesium sulfate
4. 4
   تركيزconcentrated

الإجراء التجريبي

A mixture of 1-methyl-1H-pyrazole-4-carbaldehyde (2.59 g), sodium hydride (60% in oil, 1.13 g), ethyl diethylphosphonoacetate (5.8 g) and N,N-dimethylformamide (50 ml) was stirred at room temperature for 2 hrs. The reaction mixture was poured into water, and the mixture was extracted with ethyl acetate. The organic layer was washed with water, dried over anhydrous magnesium sulfate, and concentrated. The residue was subjected to silica gel column chromatography to give ethyl (2E)-3-(1-methyl-1H-pyrazol-4-yl)acrylate (2.72 g, 64%) as crystals from a fraction eluted with hexane-ethyl acetate (1:1, v/v). Recrystallization thereof from ethyl acetate-hexane gave colorless prism crystals. melting point: 43-44° C.

المصدر