A Molecular Receptor Based on the 2,3,7,8,12,13,17,18-Octaethyl- 21,23-dimethylporphyrin for Detection of Fluoride Ions: Synthesis, Spectral and Complexation Properties

摘要

2,3,7,8,12,13,17,18-Octaethyl-21 -methylporphyrin and 2,3,7,8,12,13,17,18-octaemyl-22,23-dimethyl-porphyrin monotriflate based on the former were synthesized. Basic and complexing properties of these compounds were studied by the method of spectrophotometric titration in acetonitrile-perchloric acid and aceto-nitrile-tetrabutylammonium fluoride systems at 298 K. It was established that in the system of acetonitrile-perchloric acid the cationic forms of 2,3,7,8,12,13,17,18-octaethyl-21-methylporphyrin do not form complexes with fluoride ions, whereas 2,3,7, 8,12,13,17,18-octaethyl-22,23-dimethylporphyrin monotriflate forms complexes of 1:1 composition with the fluoride ions. The protonation constant of 2,3,7,8,12,13,17,18-octaethyl-21-methylporphyrin and the stability constant of the complex of 2,3,7,8,12,13,17,18-octaethyl-22,23-dimethyl-porphyrin with fluoride ions in acetonitrile at the standard temperature were determined.