Coordination reaction of cobaloxime with 4-vinylpyridine-styrene copolymer |
| |
Authors: | Ei-Ichi Terada Hiroshi Nishikawa Jinsh Cho Eishun Tsuchida |
| |
Institution: | Ei-Ichi Terada,Hiroshi Nishikawa,Jinshū Cho,Eishun Tsuchida |
| |
Abstract: | The equilibrium constants of the coordination reaction of chlorodimethylformamide·cobaloxime with 4-vinylpyridine–styrene copolymers (PPS) were determined. The constants for PPS, which contain 20–50% 4-vinylpyridine (4VP) unit, measured about 1.3 × 105 liter/mole larger than those in the pyridine system (6.8 × 104 liter/mole). When the polymer ligand is 4VP homopolymer or contains less than 20% 4VP unit, K values are lower. The rate constants (kf) of the coordination reactions of the cobaloxime with polymer ligands were also measured in dimethylformamide (DMF) and benzene. In DMF kf decreased with an increase in 4VP unit content of the polymer ligand; in benzene it was increased by the 4VP fraction. These results can be explained by the variation in conformation of the polymer chain in each solvent. The effect of the polymer chain on complexation was discussed on the basis of the kinetic data. |
| |
Keywords: | |
|
|