Monolithic capillary columns were prepared by transition metal-catalyzed ring-opening metathesis copolymerization of norborn-2-ene and 1,4,4a,5,8,8a-hexahydro-1,4,5,8-exo,endo-dimethanonaphthalene inside a silanized 200-microm-i.d. fused-silica capillary using a mixture of toluene and 2-propanol as porogen and Cl2(PCy3)2Ru(=CHPh) as initiator. The synthesized columns allowed the rapid and highly efficient separation of single- and double-stranded nucleic acids by ion-pair reversed-phase high-performance liquid chromatography and of proteins by reversed-phase high-performance liquid chromatography. Compared to 3-mm-i.d. analytical columns synthesized from an identical polymerization mixture, a considerable improvement in the peak widths at half-height of oligonucleotides in the order of 60-80% was obtained. Significant differences in morphology between the capillary column, where the surface of the monolith was rather soft and rugulose, and the analytical column, where the surface was very sharp and smooth, were observed, most probably due to differences in polymerization kinetics. The synthesized monoliths were successfully applied to the separation of the diastereomers of phosphorothioate oligodeoxynucleotides. To confirm the identity of the eluting compounds on the basis of their intact molecular masses, the chromatographic separation system was on-line hyphenated to electrospray ionization mass spectrometry.

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[2][3]phenyl]ethenyl]-1′,2,2′,3,3′,4,4′,5-octamethylferrocene (2) was prepared via Wittig-and chloro-Wittig-type reactions. 2 reacts with the well-defined Schrock-initiator Mo(N-2,6-Me 2C6H3)(CHCMe2Ph)(OCMe(CF3)2)2 via R-addition. The resulting class VI polymerization system allows the living polymerization of 2 up to a degree of polymerization of 150. Mesoporous and nonporous silica (Nucleosil 300-5 and Micra, respectively) with different specific surface area (100 and 2 m 2 /g, respectively) were surface-derivatized with norborn-2-en-5-yltrichlorosilane, leading to an average surface functionalization of 230 and 50 µmol norbornene/g, respectively. Monomer 2, ethynylferrocene (1), and 2-[4-(ethynyl)phenyl]ethenyl]-1′,2,2′,3,3′,4,4′,5-octamethylferrocene) (3) were surface-grafted onto these silica supports via alkyne metathesis polymerization using Mo(N-2,6-Me 2C6H3)(CHCMe2Ph)(OCMe(CF3)2)2. Typical amounts of grafted monomer were in the range 50-5 µmol/g. The resulting poly(ferrocene)-grafted supports were subsequently oxidized with iodine to the corresponding poly(ferricinium)-grafted supports and successfully used for anion-exchange chromatography of oligonucleotides (dT)12-(dT)18.

Norbornen-5-yl carboxylic acid and norbornen-5-ylmethylsilyl ether-based beta-cyclodextrins (beta-CDs) containing up to three norbornene ester and up to five norbornene silyl ether units have been prepared from beta-CD and norbornen-5-carboxylic chloride and norbornen-5-ylmethyldichlorosilane, respectively. Oligomers (n = 2-4) were prepared therefrom using ring-opening metathesis polymerization (ROMP). Monomeric and oligomeric substituted beta-CDs were evaluated as chiral selectors in nonaqueous capillary zone electrophoresis using 35 mM sodium bicarbonate in N-methylformamide (NMF) as background electrolyte. Both monomeric and oligomeric norbornene ester- and norbornene silyl ether-type selectors showed good enantioresolution for dansylated (DNS-) amino acids using concentrations of the chiral selector of up to 4% w/v. A significant improvement in resolution was observed upon the introduction of up to five norbornene silyl ether units into a beta-CD molecule, whereas higher degrees of substitution with norbornen-5-yl-carboxyl groups lead to a reduction in enantioresolution of DNS-amino acids. Thus, pentakis(norbornen-5-ylmethylhydroxysiloxyl)-beta-CD turned out to be superior to mono(norbornen-5-ylmethylhydroxysiloxyl)-beta-CD in terms of enantioresolution. Moreover, norbornene silyl ether-type selectors were found to be more efficient than norbornene ester-type selectors. Finally, oligomeric selectors were found to possess superior or at least comparable enantioselectivity in the separation of DNS-amino acids compared to the parent monomers. A maximum in enantioresolution was obtained with oligo(pentakis(norbornen-5-ylmethylhydroxysiloxyl)beta-CD).

Ring‐opening metathesis polymerization (ROMP) was used for the synthesis of monolithic capillary columns with inner diameters of 200 µm. The resulting polymeric monoliths were characterized by inverse size‐exclusion chromatography (ISEC). Surface functionalization was carried out in situ using 2‐(N,N‐dimethylaminoethyl)norborn‐5‐ene‐2‐ylcarboxylic amide (1). The resulting functionalized monoliths were successfully used in anion‐exchange chromatography of oligodeoxynucleotides.magnified image