Synthesis and characterization of a novel resorcinarene-based stationary phase bearing polar headgroups for use in reversed-phase high-performance liquid chromatography.

A novel silica-bonded stationary phase containing a functionalized resorcinarene selector was prepared by a straightforward synthesis. The complete modification of all resorcinic hydroxyl groups was achieved by reaction with isopropyl isocyanate. The derivatized resorcinarene selector was subsequently immobilized via the four alkenyl chains containing a terminal double bond by a free radical-induced reaction on mercaptopropyl-functionalized silica.

Mixed chiral stationary phase containing modified resorcinarene and beta-cyclodextrin selectors bonded to a polysiloxane for enantioselective gas chromatography.

Both a resorcinarene with pendant L-valine diamide groups (used as hydrogen-bonding selector) and a permethylated beta-cyclodextrin (used as inclusion-type selector) were chemically bonded to poly(hydromethyl)dimethylsiloxane in a one-pot reaction via Pt-catalyzed alkene hydrosilylation. This novel mixed chiral stationary phase (mixCSP) named Chirasil-Calixval-Dex resembles a combination of the known chiral stationary phases (CSPs) Chirasil-Calixval and Chirasil-Dex and it was used successfully in enantioselective gas chromatography toward a unified enantioselective GC separation system. It is demonstrated that Chirasil-Calixval-Dex retains the individual enantioselectivites of the single components.