Straightforward Synthesis of Poly(dimethylsiloxane) Phases with Immobilized (1 R )‐3‐(Perfluoroalkanoyl)camphorate Metal Complexes and Their Application in Enantioselective Complexation Gas Chromatography

A straightforward synthesis of novel chiral polysiloxane‐based metal stationary phases immobilized through a propylenoxy linker (Chirasil‐Metal‐OC 3 ) to the polymeric backbone is presented. Synthesis was accomplished in six steps with high overall yields starting from commercially available, enantiopure (+)‐(1 S )‐camphorsulfonic acid. Two different approaches towards Chirasil‐Metal phases featuring either a propylenoxy or propylenthio linker used for immobilization through hydrosilylation are presented. Furthermore, a new protocol for the fluoroacylation, which is one of the key steps in the synthesis of (1 R )‐3‐(perfluoroalkanoyl)camphorate metal complexes, was developed to improve the isolation and overall yield. The immobilization of (1 R ,4 S )‐10‐(allyloxy)‐3‐(heptafluorobutanoyl)camphor – 10‐(allyloxy)‐hfbc – onto polysiloxanes as well as the incorporation of nickel(II), oxovanadium(IV), europium(III), and lanthanum(III) was characterized by FT ATR IR and NMR spectroscopy. Overall, seven different Chirasil‐Metal‐OC 3 polymers with different separation properties were prepared by metal incorporation and variation of the amount of immobilized (1 R ,4 S )‐10‐(allyloxy)‐3‐(heptafluorobutanoyl)camphor (10‐allyloxy‐hfbc: 3.5, 10.2, and 20.0 %). Their performance in enantioselective complexation gas chromatography was systematically studied and excellent enantioselectivity was found for Chirasil‐Nickel‐OC 3 . Separation of 29 small‐sized compounds, encompassing, among others, epoxides, substituted alkenes and alkynes as well as alcohols and amides, was achieved with high separation factors α . The synthetic strategy, enantiomer separations and thermal stability (up to 160 °C) demonstrates the versatility of the newly derived Chirasil‐Metal‐OC 3 phases.