Enantioselective Synthesis of α-Benzylalanine Using trans-3,4-Dihydro-3,4-diaryldibenzo[c,g]phenanthrene-3,4-diols

Abstract

Asymmetric benzylation of a benzophenone Schiff’s base of alanine ethyl ester was successfully conducted using trans-3,4-dihydro-3,4-diaryldibenzo[c,g]phenanthrene-3,4-diol as a chiral source.

amino acids - asymmetric synthesis - biaryls - diols - phase-transfer catalysis

References and Notes

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12

In an initial screening on bases (NaH, KH, CaH₂, NaOH, KOH, CsOH˙H₂O, CsCO₃, t-BuONa, t-BuOK), t-BuOK was good in terms of the yield and/or ee of the alkylated product 4.

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