SOME THOUGHTS ON THE COUPLING OF DISSIMILAR CHIRAL COLUMNS OR THE MIXING OF CHIRAL STATIONARY PHASES FOR THE SEPARATION OF ENANTIOMERS

Consideration of some basic aspects of the separation of enantiomers o n chiral stationary phases suggests that the coupling of dissimilar ch iral columns to afford a broad-spectrum screen for the separation of o therwise pure enantiomers cannot be recommended. However, this arrange ment can sometimes be useful for the separation of enantiomers in comp lex mixtures. An analysis of various arrangements is discussed, includ ing tandem column arrangements containing dissimilar chiral packings, columns containing mixed packings or mixed selectors, and the use of c olumns containing selectors of varying degrees of enantiopurity.