Transition metal complex stationary phases for the CGC analysis of ethers, thioethers and ketones

Abstract

SummaryThe use of polysiloxanes with cyano or thiol groups as stationary phases for complexation gas chromatography is discussed. The polymers were obtained via polycondensation followed by polymerisation of the corresponding dichloro-or dimethoxy-silanes. Both the phases were modified by bonding transition metal chlorides with cyano (CuC12 or COC12) and thiol groups (NiC12 or COC12). The phases were examined in order to determine their application to the analysis of ethers, thioethers and ketones. Due to the presence of lone electron pairs on oxygen or sulphur atoms, the compounds should be capable of specific interacting with the electron-withdrawing centre of the liquid stationary phases. A number of retention parameters (retention indices, molecular retention indices and specific retention volume) were determined, which allowed characterisation of specific interactions between the bonded metal and the compound analysed. The results also enabled assessment of the influence of the structure of the compounds on their retention. The measurements were also carried out for the phases with free SH and CN groups as reference phases. The work demonstrates that the phases obtained may be useful for effective separations.

Capillary complexation gas chromatography in analysis of cyclic and aromatic hydrocarbons

“…The interactions between the phases and the hydrocarbons are described using the following parameters: retention coefficient (k), retention index (/), molecular retention index (AMe) and specific retention volume (Vg). Results of similar studies obtained for ethers, thioethers, ketones and halogeno-hydrocarbons were discussed in our earlier work [5,6]. …”