Synthesis And Properties Of Chiral Calix[4]arenes

Calixarenes are a class of marcrocycles derived from the condensation of phenols and formaldehyde. As the third generation host compounds, the study of them in the fields such as molecule recognition, assemble and enzyme mimics has been made great progress. The chiral calixarenes attract increasing interest in these years because of their special conformation. So some work on synthesis and properties study of chiral calixarenes had been done. New chiral calixarenes connected optical pure aminol groups and optical pure amine groups at low rim were synthesized by the reaction of optical pure α, β-amino alcohol or methylbenzylamine with calix[4]arene dibromide prepared by the reaction of 4-tert-butylcalix[4]arene with 1, 2-dibromoethane, which characterized by IR,1H NMR,13C NMR and ESI+ HRMS. The results demonstrate that they are in cone conformation.(1'R, 2'S)-5,11,17,23-Tetra-tert-butyl-25,27-dihydroxy-26,28-di(1', 2'-diphenyl-2'- hydroxyethyl-aminoethoxy)calix[4]arene can form 1:1 dimer by self-assembly in d-methanol and the association constant of the dimer is 34.7 M-1 determined by 1H NMR titration.The chiral recognition ability of these chiral calixarenes were measured by 1H NMR spectra. It is found that these chiral calixarenes containing aminol groups have an exceptional chiral recognition ability between the enantiomers of benzoyltartaric acid, mandelic acid, 2-hydroxyisovaleric acid and the chiral calixarene containing amine group has chiral recognition ability between the enantiomers of benzoyltartaric acid, mandelic acid. Chiral calyx [4]arenas containing acylamide group were synthesized by the reaction of calix[4]arene with halides which prepared by chiral compounds containing amine group with chloroacetyl chloride. These chiral calix[4]arenas characterized by IR,1H NMR,13C NMR. The results demonstrate that they are in cone conformation.