反应详情

To guanidine hydrochloride (25.4 kg, 266 mole) in methanol (60 litres) was added 30% w/w sodium methoxide in methanol solution (49.2 kg, 273.3 mole). The suspension was heated to 55° C.±2° C. The toluene solution of 2-(2,3-dichlorophenyl)-3-ethoxy-4-fluoro-2-butenenitrile was added over a period of 45 minutes and the resultant mixture was boiled under reflux for 4 hours, cooled then quenched into water (230 litres). The solid precipitate was washed with 5 portions of methanol (25 litres) to yield the racemate as an off white solid (26.3 kg, 38% yield from 2,3-dichlorophenylacetonitrile).

1. temperatureThe suspension was heated to 55° C.±2° C
2. temperatureunder reflux for 4 hours
3. temperaturecooled
4. customthen quenched into water (230 litres)
5. washThe solid precipitate was washed with 5 portions of methanol (25 litres)