Backbone Modification of Chirasil-Val, Part II

Published: Journal of Chromatographic Science, Volume 33, Number 5, May 1995, pp. 217-222.

Backbone Modification of Chirasil-Val, Part II: Introduction of a Rigid Cyclohexyl Spacer
Bernhard Koppenhoefer, Ulrich Mühleck, Michael Walser, and Konrad Lohmiller

The polysiloxane backbone of the gas chromatographic phase Chirasil-Val is modified by introducing a rigid spacer. Thus, improved shielding of the chiral moiety from the achiral polysiloxane units is achieved. The new phase, Chirasil-Nova-CH, is prepared by coupling 4-exomethylen cyclohexyl carboxylic acid to l-valine tert-butylamide, followed by hydrosilylation with a copolymer containing Si–H groups. As compared with Chirasil-Nova bearing the linear spacer (CH₂)₃, the new phase, Chirasil-Nova-CH with a cyclohexyl spacer, shows an advantageous shortening of retention times without an apparent loss in the resolution factors for the enantiomers of amino acid derivatives.

Reproduction of editorial content of this journal is prohibited without publisher’s permission.

This article is available in its entirety by fax for $40.00.
Visa, MasterCard & Amex accepted.

To order electronically click here
or call: 847-647-2900 ext. 1323
or fax request to: 847-647-1155.

To order multiple copies click here.

Please indicate JCS volume and issue along with page numbers.