Enantiomeric recognition of amino acid salts by macrocyclic crown ethers derived from enantiomerically pure 1,8,9,16-tetrahydroxytetraphenylenes

J Org Chem. 2013 Sep 6;78(17):8562-73. doi: 10.1021/jo401240k. Epub 2013 Aug 22.

Abstract

Asymmetric synthesis of (R,R)- and (S,S)-1,8,9,16-tetrahydroxytetraphenylenes was achieved from starting material (2R,3R)-butane-2,3-diol and (2S,3S)-butane-2,3-diol respectively by utilizing a center-to-axis strategy. A series of crown ether compounds 20, 24, and 25 and their corresponding enantiomers derived from chiral tetrahydroxytetraphenylene were synthesized in enantiomerically pure forms. Enantiomeric recognition properties of these hosts toward l- and d-amino acid methyl ester hydrochloride were studied by the UV spectroscopy titration. The tetramer hosts (S,S,S,S,S,S,S,S)-20 and (R,R,R,R,R,R,R,R)-20 exhibited the best enantioselectivities toward L- and D-alanine methyl ester hydrochloride salt with K(L)/K(D) = 4.1 and KD/KL = 3.9, respectively. The new chiral macrocyclic hosts would further enrich the host-guest chemistry.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / chemistry*
  • Crown Ethers / chemical synthesis
  • Crown Ethers / chemistry*
  • Macrocyclic Compounds / chemical synthesis
  • Macrocyclic Compounds / chemistry*
  • Models, Molecular
  • Molecular Conformation
  • Phenols / chemical synthesis
  • Phenols / chemistry*
  • Salts / chemistry
  • Stereoisomerism
  • Terphenyl Compounds / chemical synthesis
  • Terphenyl Compounds / chemistry*

Substances

  • Amino Acids
  • Crown Ethers
  • Macrocyclic Compounds
  • Phenols
  • Salts
  • Terphenyl Compounds