Calix[4]arene-based bis[2]catenanes: synthesis and chiral resolution

Chemistry. 2007;13(21):6157-70. doi: 10.1002/chem.200601814.

Abstract

The exclusive formation of hydrogen-bonded dimers between tetraaryl and tetratosylurea calix[4]arenes has been used to prepare a series of ten "bisloop" tetraurea calix[4]arenes 3, in which adjacent phenylurea groups are covalently linked through alpha,omega-dioxyalkane chains. This dimerization with tetratosylurea 2 as template preorganizes the alkenyl residues of tetra(m-alkenyloxyphenyl) ureas 1 and enables their selective connection in high yield (up to 95 %) by olefin metathesis followed by hydrogenation. The "bisloop" calixarenes 3 also exclusively form heterodimers with 1. Thus, in a separated metathesis/hydrogenation sequence, a series of 14 cyclic bis[2]catenanes 4, in which two calix[4]arenes are connected through their wide rims by two pairs of interlocked rings (total size 29 to 41 atoms), were prepared in yields of up to 97 %. Optical resolution of these chiral bis[2]catenanes was studied by HPLC on chiral stationary phases. The single-crystal X-ray structure of one example (4(P,10)) confirmed the interlocking rings and revealed that the hydrogen-bonded dimeric capsule of the calix[4]arene can be "completely" opened.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Calixarenes / chemical synthesis
  • Calixarenes / chemistry*
  • Catenanes / chemistry*
  • Crystallography, X-Ray
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Molecular Structure
  • Stereoisomerism

Substances

  • Catenanes
  • Calixarenes