Direct optical resolution of the enantiomers of axially chiral compounds by high-performance liquid chromatography on cellulose tris-(3,5-dimethylphenylcarbamate) stationary phase

The enantiomeric separation of nineteen biphenyl dimethyl dicarboxylate der ivatives has been examined by HPLC on a chiral stationary phase prepared by coating aminopropylated silica gel with cellulose tris-(3,5-dimethylphenyl carbamate). It was found that trifluoroacetic acid (TFA) has a dominant eff ect on chiral separation for acidic compounds. The percentage of 2-propanol in the mobile phase does not have a large effect on the enantioselectivity but the separation was dramatically influenced by the kind of alcohol in t he mobile phase. The effect of temperature on the chiral separation is also discussed. Most of the enantiomers investigated could be resolved satisfac torily.