Diastereoselective and Enantioselective Synthesis of Unsymmetric β,β-Diaryl-α-Amino Acid Esters via Organocatalytic 1,6-Conjugate Addition of para-Quinone Methides.

  title={Diastereoselective and Enantioselective Synthesis of Unsymmetric $\beta$,$\beta$-Diaryl-$\alpha$-Amino Acid Esters via Organocatalytic 1,6-Conjugate Addition of para-Quinone Methides.},
  author={Xiang‐Zhi Zhang and Yuhua Deng and Xu Yan and Ke‐Yin Yu and Fang-Xin Wang and Xiao-Yan Ma and Chun‐An Fan},
  journal={The Journal of organic chemistry},
  volume={81 13},
A novel strategy based on phase transfer catalysis for the diastereoselective and enantioselective direct assembly of unsymmetric β,β-diaryl-α-amino acid esters via 1,6-conjugate addition of para-quinone methides and glycine derivatives is described. This protocol also provides an alternative route to the synthetically interesting functionalized chiral tetrahydroisoquinoline and its analogues. 
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