Facile synthesis of optical pure fenoxaprop-p-ethyl[ethyl (R)-2-{4-(chloro-1,3-benzoxazol-2-yloxy)phenoxy}propionate]

광학활성 제초제 fenoxaprop-p-ethyl [ethyl (R)-2-{4-(6-chloro-1,3-benzoxazol-2-yloxy)phenoxy}propionate]의 새로운 합성법

  • 류성곤 (한국화학연구원 생물화학연구부) ;
  • 고영관 (한국화학연구원 생물화학연구부) ;
  • 장해성 (한국화학연구원 생물화학연구부) ;
  • 류재욱 (한국화학연구원 생물화학연구부) ;
  • 우재춘 (한국화학연구원 생물화학연구부) ;
  • 구동완 (한국화학연구원 생물화학연구부) ;
  • 김대황 (한국화학연구원 생물화학연구부) ;
  • 정근회 (한국화학연구원 생물화학연구부)
  • Published : 2004.03.30


Fenoxaprop-p-ethyl[Ethyl (R)-2-{4-(6-chloro-1,3-benzoxazol-2-yloxy)phenoxy}propionate] is well known as a herbicide for its specific activity against the weed grasses. This compound was synthesized by the reaction of 4-(6-chloro-1,3-benzoxazol-2-yloxy)phenol and ethyl (S)-O-(p-toluenesulfonyl)lactate in good yields with high optical pure(optical purity: 99.9% up). In this process Walden inversion occurs, whereby the S-configuration of the propionic acid derivative is converted to the R-configuration of the final product. 4-(6-Chloro-l,3-benzoxazol-2-yloxy)phenol was obtained by 5 step reactions in over-all 70% yields using inexpensive raw materials.


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