Effect of the double bond pi-conjugation of the aromatic group of racemic analytes on the liquid chromatographic separation of enantiomers

Various arylcarbinol esters were resolved on a commercial chiral column, (S , S) Whelk-Ol. Among others, the analytes in which the aryl group is in con jugation with the double bond(s) to the chiral center were resolved much be tter on (S,S) Whelk-Ol than the corresponding non-double bonded analytes. F rom these results, it was proposed that the double bond pi -conjugation of the aromatic group of racemic analytes is very important for the chiral rec ognition. In addition, the size of the acyl group of arylcarbinol esters ha s been demonstrated to be important for the chiral recognition. In general, the large acyl group such as pivaloyl group was very effective for the chi ral recognition of arylcarbinol esters on (S,S) Whelk-Ol.