A trans influence and π-conjugation effects on ligand substitution reactions of Pt(II) complexes with tridentate pendant N/S-donor ligands
| dc.contributor.author | Kinunda, Grace | |
| dc.date.accessioned | 2018-09-17T10:34:18Z | |
| dc.date.available | 2018-09-17T10:34:18Z | |
| dc.date.issued | 2018 | |
| dc.description.abstract | The rate of displacement of the chloride ligands by three neutral nucleophiles (Nu) of different steric demands, namely thiourea (TU), N,N’-dimethylthiourea (DMTU) and N,N,N,’N-tetramethylthiourea (TMTU) in the complexes viz; [Pt(II)(bis(2-pyridylmethyl)amine)Cl]ClO4, (Pt1), [Pt(II){N-(2-pyridinylmethyl)-8-quinolinamine}Cl]Cl, (Pt2), [Pt(II)(bis(2-pyridylmethyl)sulfide)Cl]Cl, (Pt3) and [Pt(II){8-((2-pyridylmethyl)thiol)quinoline}Cl]Cl, (Pt4) was studied under pseudo first-order conditions as a function of concentration and temperature using a stopped-flow technique and UV-Visible spectrophotometry. The observed pseudo first-order rate constants for substitution reactions obeyed the simple rate law. The results have shown that the chloro ligand in Pt(N^S^N) complexes is more labile by two orders of magnitude than Pt(N^N^N) complexes due to the high trans labilizing effect brought by the S-donor atom. The quinoline based Pt(II) complexes (Pt2 and Pt4) have been found to be slow than their pyridine counterparts Pt1 and Pt3 due to poor π-acceptor ability of quinoline. Second-order kinetics and large negative activation entropies support an associative mode of activation. | en_US |
| dc.identifier.citation | Kinunda, G. A. (2018). A trans influence and π-conjugation effects on ligand substitution reactions of Pt (II) complexes with tridentate pendant N/S-donor ligands. Tanzania Journal of Science, 44(2), 45-64. | en_US |
| dc.identifier.uri | http://hdl.handle.net/20.500.11810/4903 | |
| dc.language.iso | en | en_US |
| dc.publisher | College of Natural and Applied Sciences | en_US |
| dc.subject | Substitution | en_US |
| dc.subject | nucleophiles | en_US |
| dc.subject | pseudo first-order | en_US |
| dc.subject | associative | en_US |
| dc.subject | entropy | en_US |
| dc.title | A trans influence and π-conjugation effects on ligand substitution reactions of Pt(II) complexes with tridentate pendant N/S-donor ligands | en_US |
| dc.type | Journal Article, Peer Reviewed | en_US |