Spirocyclopropanation Reaction of para-Quinone Methides with Sulfonium Salts: The Synthesis of Spirocyclopropanyl para-Dienones.

  title={Spirocyclopropanation Reaction of para-Quinone Methides with Sulfonium Salts: The Synthesis of Spirocyclopropanyl para-Dienones.},
  author={Xiang‐Zhi Zhang and Ji-Yuan Du and Yuhua Deng and Wen-Dao Chu and Xu Yan and Ke‐Yin Yu and Chun‐An Fan},
  journal={The Journal of organic chemistry},
  volume={81 6},
A novel DBU-mediated stereoselective spirocyclopropanation of para-quinone methides with sulfonium salts has been developed on the basis of the mode involving a 1,6-conjugate addition/intramolecular dearomatizing cyclization cascade. This reaction provides a mild and effective method for the assembly of synthetically and structurally interesting spirocyclopropanyl para-dienones. The feasibility for the enantioselective access to such functionalized para-dienones has also been explored by using… 

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