反应详情

温度

60 °C

Water (20 mmoles) is added to a solution of 1,1,1,3-tetrachloro-3-ethoxypropane (10 mmoles) in dimethoxyethane (25 ml). The mixture is stirred for 2 h at 60° C. The resulting mixture is slowly added to a mixture consisting of a pyrazine-2-carboxamidine hydrochloride (10 mmoles). 2-difluoromethoxypyridin-4-ol (10 mmoles), potassium carbonate (60 mmoles) and dimethoxyethane (50 ml), which is stirred under reflux. When the addition of 3,3-dichloroacrolein solution is completed additional pyrazine-2-carboxamidine hydrochloride (0.5 mmoles) is added. The reaction mixture is stirred for 2 hours under reflux and subsequently cooled down to ambient temperature, filtered through silica, and the organic phase is concentrated in vacuo. The residue is purified by chromatograph on SiO2 (ethyl acetate) to yield 2,60 g (82%) of beige crystals having a melting point of 128-129° C.

1. additionThe resulting mixture is slowly added to a mixture
2. temperatureunder reflux
3. additionis added
4. stirringThe reaction mixture is stirred for 2 hours
5. temperatureunder reflux
6. temperaturesubsequently cooled down to ambient temperature
7. filtrationfiltered through silica
8. concentrationthe organic phase is concentrated in vacuo
9. customThe residue is purified by chromatograph on SiO2 (ethyl acetate)