Phenyl Functional Groups Research Articles

Porphyrin chemistry pertaining to the design of anti-cancer drugs; part 1, the synthesis of porphyrins containing meso-pyridyl and meso-substituted phenyl functional groups

Condensation of pyrrole with a benzaldehyde and 4-pyridinecarboxaldehyde mixture yields the six possible meso-substituted phenyl or pyridyl porphyrins. Nitration of four of these has yielded 13 other porphyrins containing one to four 4-nitrophenyl moieties, and SnCl2 reduction of eight of these nitrophenylporphyrins gives the corresponding 4-aminophenyl(phenyl)- or 4-aminophenyl(phenyl)(4-pyridyl)-porphyrins. Twelve of the porphyrins are new, but all 27 are fully characterized by 1H NMR; resonances for every proton within each of the phenyl, pyridyl, and pyrrole rings are assigned. Trends in UV–VIS data are discussed, while IR and mass spectral data are noted for selected porphyrins.

Liquid chromatography—electrochemistry procedure for the determination of chlorophenolic compounds in pulp mill effluents and receiving waters

An isocratic, reversed-phase liquid chromatography procedure is described for the separation and determination of chlorophenolic compounds, including several priority pollutant chlorophenols. The separation was experimentally optimised, and selective and sensitive detection was obtained by dual electrode amperometry. The most suitable combination was a silica-based column with phenyl functional groups, and a mobile phase of acetonitrile-acetate buffer (40:60, pH 5). Dual glassy-carbon electrodes were used in a parallel configuration in a thin-layer flow cell, with differential current measurement (+0.90 V relative to +0.60 V). A solid-phase extraction scheme using a polymeric sorbent (Chromosorb 102) was devised for the extraction and preconcentration of selected chlorophenols, chloroguaiacols, and a chlorosyringol from aqueous samples. Use of tribromophenol as an internal standard was also investigated. The total procedure —preconcentration and chromatography— was applied to the analysis of effluents discharged by a paper mill, and a pulp mill.

Deactivation of fused silica capillary columns with phenylhydrosiloxanes

AbstractIn this work, an investigation of new organosilicon hydride reagents with phenyl functional groups for deactivation and surface modification of fused silica capillary columns is described. Different reagents were tested for their ability to deactivate the fused silica surface, and actual critical surface tension measurements were made using the capillary rise method. The deactivation procedure required lower optimum temperatures than conventional methods. Deactivated capillaries and coated capillary columns were prepared and tested for reproducibility, efficiency, and surface inertness towards basic and acidic compounds at the low nanogram level.

Deactivation of fused silica capillary columns with polymethylhydrosiloxanes

In this work, an investigation of new organosilicon hydride reagents with phenyl functional groups for deactivation and surface modification of fused silica capillary columns is described. Different reagents were tested for their ability to deactivate the fused silica surface, and actual critical surface tension measurements were made using the capillary rise method. The deactivation procedure required lower optimum temperatures than conventional methods. Deactivated capillaries and coated capillary columns were prepared and tested for reproducibility, efficiency, and surface inertness towards basic and acidic compounds at the low nanogram level.