Evaluating a New Chlorinated Polysaccharide Chiral Stationary Phase for Improved Selectivity: The RegisPack CLA-1

June 1, 2010

The Application Notebook

The Application Notebook, The Application Notebook-06-01-2010, Volume 0, Issue 0

Polysaccharide-based chiral stationary phases (CSPs) and Pirkle-type CSPs are often successful in achieving a majority of analytical and preparative chiral separations.

Ted Szczerba, Regis Technologies, Inc.

Polysaccharide-based chiral stationary phases (CSPs) and Pirkle-type CSPs are often successful in achieving a majority of analytical and preparative chiral separations. However, there are a few cases in which these proven chiral selectors lead to partial, poor, or no separation at all. The new RegisPack® CLA-1 addresses some of these issues.

This study used three well-established CSPs (Whelk-O® 1, RegisPack®, RegisCell®) and the new RegisPack® CLA-1. All phases were based on 5-micron silica.

Figure 1

The Whelk-O® 1 (a Pirkle-type CSP) is based on 1-(3,5-dinitrobenzamido)-1,2,3,4-tetrahydrophenathrene.

The RegisPack® and RegisCell® are coated with tris-(3,5-dimethylphenyl) carbamate of amylose and tris-(3,5-dimethylphenyl) carbamate of cellulose, respectively.

The new chlorinated RegisPack® CLA-1 is coated with tris-(5-chloro-2-methylphenyl) carbamate of amylose.

This study used two compounds that were previously difficult to separate on existing CSPs. We explored the possibility of baseline resolving the diastereomers of cyclandelate, and to achieve a baseline separation of acebutolol. Although we achieved partial separation, we were not able to fully resolve these two compounds on existing CSPs. The new RegisPack® CLA-1 was able to help us with this problem. Following are some chromatograms that show excellent baseline separation of our test compounds.

Figure 2

Conclusion

The Whelk-O® 1, RegisPack®, and RegisCell® CSPs are well-established phases that do a superior job of separating the majority of compounds submitted for chiral screening. There are cases where these CSPs can only achieve partial or no separation on some analytes. The new RegisPack® CLA-1 exhibits unique selectivity in separation when existing CSPs fail.

Regis Technologies, Inc.

8210 Austin Ave, Morton Grove , IL 60053

tel. (847)583-7661; fax (847)967-1214

Email: teds@registech.com, Website: www.registech.com/chiral/