Chiral recognition between a substituted cyclooctatetraene dianion and a half crown ether substituted with ibuprofen

J Org Chem. 2000 Nov 3;65(22):7588-94. doi: 10.1021/jo000972p.

Abstract

(S)-Verbenol was substituted onto cyclooctatetraene (COT) via an ether linkage. In tetrahydrofuran (THF), Cs(+) or Na(+) counterions are tightly ion associated with the verbenoxy-COT dianion. A cosolvent, consisting of an ibuprofen unit connected to a half crown ether, was added to the verbenoxy-COT(2)(-),M(+)(2) solutions. The intimate interaction between the chiral cosolvent (ibuprofoxymethoxyethoxyethane) and the ion-associated counterion (either Na(+) or Cs(+)) forces a chiral recognition between the verbenoxy moiety and the ibuprofoxy moiety. When a molar excess of the cosolvent is present in the dianion THF solution, separation of the cosolvent associated with the verbenoxy-COT(2)(-),M(+)(2) complex from the uncomplexed cosolvent allows partial resolution of the enantiomers of ibuprofoxymethoxyethoxyethane.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Algorithms
  • Electron Spin Resonance Spectroscopy
  • Ethers, Cyclic / chemical synthesis
  • Ethers, Cyclic / chemistry*
  • Ibuprofen / chemical synthesis
  • Ibuprofen / chemistry*
  • Magnetic Resonance Spectroscopy
  • Stereoisomerism

Substances

  • Ethers, Cyclic
  • Ibuprofen