Regioselective carbamoylated and benzoylated cellulose for the separation of enantiomers in high-performance liquid chromatography

The preparation of new chiral stationary phases (CSPs) based on mixed substituted cellulose is reported. The first type of CSP has a 3,5-dimethylphenylcarbamate at the 2 and 3 positions and a phenylethylcarbamate at the 6 position. The second one has a benzoate at the 2 and 3 positions and a meta-substituted phenylcarbamate at the 6 position. The last one has a 3,5-dimethylphenylcarbamate at the 2 and 3 positions and a para-substituted benzoate at the 6 position. This work shows that the substituent present at the 6 position is very important for chiral recognition. Some of the new CSPs exhibit a better enantioselective power for several racemates compared to the corresponding Chiralcel columns. The resolution of some beta-adrenergic blockers and benzodiazepines is also reported.