Synthesis of cyclobakuchiols A, B, and C by using conformation-controlled stereoselective reactions.

  title={Synthesis of cyclobakuchiols A, B, and C by using conformation-controlled stereoselective reactions.},
  author={Hidehisa Kawashima and Yuki Kaneko and Masahiro Sakai and Yuichi Kobayashi},
  volume={20 1},
Cyclohexanone with the pMeOC6H4 and CH2=C(Me) substituents at the C3 and C4-positions was prepared from (+)-β-pinene and converted to the allylic picolinate by a Masamune-Wittig reaction followed by reduction and esterification. Allylic substitution of this picolinate with Me2CuMgBr·MgBr2 in the presence of ZnI2 proceeded with γ regio- and stereoselectively to afford the quaternary carbon center on the cyclohexane ring with the CH2=CH and Me groups in axial and equatorial positions… 
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