Direct oxidative cyclization of 3-arylpropionic acids using PIFA or Oxone: synthesis of 3,4-dihydrocoumarins
摘要:
The direct oxidative cyclization of 3-arylpropionic acids using PIFA or Oxone is reported. In the presence of BF(3)center dot OEt(2), the reaction of 3-arylpropionic acids with PIFA or Oxone proceeded smoothly at 30 degrees C to give 3,4-dihydrocoumarins in good to excellent yields. (C) 2009 Elsevier Ltd. All rights reserved.