Dicyanobiphenyl polysioloxane stationary phases for capillary column gas chromatography

Abstract

SummaryThe chromatographic performance of newly developed dicyanobiphenyl polysiloxane stationary phases were evaluated and compared with the performance of other polar stationary phases, including the previously reported monocyanobiphenyl polysiloxanes. Due to the unique combination of polarizable biphenyl and polar cyano functionalities in the side chains of the flexible polysiloxane backbone, and by virtue of their mild liquid crystalline properties, the new stationary phases provide excellent resolution of a wide variety of analytes, both polar and nonpolar, in both GC and SFC. They can be easily coated and cross-linked in open tubular columns, and the resultant columns demonstrate excellent efficiency and performance at temperatures up to 280-300 ~ The new stationary phases exhibit enhanced selectivities for various types of isomeric compounds.

meso,meso‐Linked and Triply Fused Diporphyrins with Mixed‐Metal Ions: Synthesis and Electrochemical Investigations

“…As before there is a small anodic shift of 30 mV each for the first and second oxidation potential when comparing tf (CN) 4 ZnCuP 2 (20) with the copper-free tf (CN) 4 ZnH 2 P 2 (18). The same trend of a slightly facilitated oxidation of copper porphyrins compared to the free-base, is observed for 18 with respect to tf (CN) 4 Zn 2 P 2 (16).…”

“…Tetracyano-substituted Zn II porphyrin (CN) 4 ZnP (3) was synthesized in a Suzuki cross-coupling between diiodoporphyrin 22 [5b,5d] and boronate 23, obtained from 5-bromo-phthalonitrile [18] and bis(pinacolato) diboron (Scheme 1). Demetallation with TFA provided the free-base porphyrin (CN) 4 H 2 P (5), which was remetallated with Cu(OAc) 2 in MeOH/CHCl 3 to give (CN) 4 CuP (4).…”

Synthesis and characterization of diphenyl–phenyl polysiloxane as a high-temperature gas chromatography stationary phase

“…These compounds were eluted in the order of their increasing dispersion force, which was in agreement with dicyanobiphenyl polysiloxane. 8 This result may be attributed to the participation of the diphenyl-phenyl group, which contains conjugated p-bonds. Given that most of these PAHs are major environmental pollutants, the DPPP-25 column can be widely used for environmental monitoring.…”

Supercritical Fluid and Unified Chromatography

“…Malik et al developed and evaluated a dicyanobiphenylsubstituted polysiloxane stationary phase suitable for open-tubular columns used in SFC (24). Because of the combination of polarizable and polar functional groups, this phase works well with a wide variety of analytes.…”