반응 #74839

반응 방정식

3,4-difluorobenzoylacetonitrile

triethyl orthoacetate

acetic

→

title compound

2-(3,4-Difluorobenzoyl)-3-hydroxycrotononitrile

용매

water

반응 조건

후처리

1. 1
   workup.ADDITIONpoured into 200 ml
2. 2
   온도On cooling
3. 3
   여과the solid is filtered
4. 4
   workup.DISSOLUTIONdissolved in methylene chloride
5. 5
   추출This solution is extracted with two portions of aqueous sodium bicarbonate
6. 6
   추출The precipitate is extracted into methylene chloride
7. 7
   온도heated
8. 8
   workup.ADDITIONdiluted with hexane
9. 9
   온도Upon cooling
10. 10
    기타colorless crystals result

실험 절차

A solution of 10.2 g. of 3,4-difluorobenzoylacetonitrile, 9.2 g. of triethyl orthoacetate and 20 ml. of acetic anhyride is heated on a steam bath for 0.5 hour and then poured into 200 ml. of water which is then heated on the steam bath for 2 hours. On cooling, the solid is filtered and then dissolved in methylene chloride. This solution is extracted with two portions of aqueous sodium bicarbonate and the aqueous extracts are combined and acidified with concentrated hydrochloric acid. The precipitate is extracted into methylene chloride, passed through a pad of Magnesol®, heated and diluted with hexane. Upon cooling, colorless crystals result, yielding the title compound, m.p. 51°-54° C.

출처