Substitution Reactions of Five-coordinate Complexes. 2. Mechanism of Ligand Replacement in Trigonal-bipyramidal Nickel(II) and Platinum(II) Complexes Containing the Tetradentate Ligand Tris(o-(diphenylarsino)phenyl)arsine

Author

Harvest L. Collier, Missouri University of Science and TechnologyFollow
Eugene B. Grimley

Abstract

Ligand replacement of the monodentate ligand in a series of trigonal-bipyramidal nickel(II) complexes containing the tetradentate ligand tris(o-(diphenylarsino)phenyl)arsine, QAS, is reported for methanol solutions. Entering ligands replacing Br^- in order of decreasing rate were SC(NH₂)² ≫ CN^-, > N3^- > SCN^- > I^- > NO₂ ^- ≫ PPh₃. CN^- replacement of leaving groups in order of decreasing rate were NCS^- > N₃ ^- > Cl^- > Br^- > NO₂ ^- > I^-. A second consecutive decomposition was observed to be several orders of magnitude slower than ligand replacement when CN^- was the entering ligand. The kinetic data obtained at 0.050 M ionic strength and 25.0°C are consistent with either an associative interchange, I_a, mechanism or a mechanism involving formation of a four-coordinate intermediate via partial dissociation of the tetradentate ligand.

Recommended Citation

H. L. Collier and E. B. Grimley, "Substitution Reactions of Five-coordinate Complexes. 2. Mechanism of Ligand Replacement in Trigonal-bipyramidal Nickel(II) and Platinum(II) Complexes Containing the Tetradentate Ligand Tris(o-(diphenylarsino)phenyl)arsine," Inorganic Chemistry, vol. 19, no. 2, pp. 511 - 515, American Chemical Society (ACS), Feb 1980.

The definitive version is available at https://doi.org/10.1021/ic50204a046

Department(s)

Chemistry

International Standard Serial Number (ISSN)

0020-1669

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 1980 American Chemical Society (ACS), All rights reserved.

Publication Date

01 Feb 1980