Azophenolic crown ethers (S,S)-1, (R,R)-2 and (S,S)-3 have been prepared in enantiomerically pure forms by using (S)-1-(1′-adamantyl)ethane-1,2-diol, (R)-3,3-dimethylbutane-1,2-diol and (S)-propane-1,2-diol, respectively, as chiral subunits, and the association constants for their complexes with chiral amines have been determined by 1H NMR or UV-VIS spectroscopic methods at various temperatures. The enantiomer selectivities of crown ethers (S,S)-1 and (R,R)-2 in complexation with 2-aminopropan-1-ol are reversed at ca. 6°C and increase with increasing temperature above the isoenantioselective temperature.
|Number of pages||9|
|Journal||Journal of the Chemical Society. Perkin Transactions 2|
|State||Published - 1 Sep 1997|