Proton NMR Kinetic Study of Ligand Exchange on Bis(1,4-dithiane)platinum(II), Bis(1,4-dithiane)palladium(II) and Tetrakis(dimethylsulfide)platinum(II) : High Presssure NMR Kinetics 51
(1991) In Inorganic Chemistry 30(26). p.5033-5037- Abstract
- Ligand exchange on square-planar Pt(1,4-dithiane)2(2+), Pd(1,4-dithiane)2(2+), and Pt(Me2S)4(2+) has been studied as a function of temperature and pressure by H-1 NMR line-broadening, isotopic labeling, and magnetization transfer experiments with deuteriated nitromethane as solvent. Second-order rate constants and activation parameters are as follows: for 1,4-dithiane exchange on Pt(1,4-dithiane)2(2+), k2(298) = 28.8 +/- 4.8 m-1 s-1, DELTA-H double-ended dagger = 32.9 +/- 3.6 kJ mol-1, DELTA-S double-ended dagger = -106 +/- 11 J K-1 mol-1, and DELTA-V double-ended dagger = -12.6 +/- 1.1 cm3 mol-1; for 1,4-dithiane exchange on Pd(1,4-dithiane)2(2+), k2(298) = 9780 +/- 300 m-1 s-1, DELTA-H double-ended dagger = 22.9 +/- 0.6 kJ mol-1, DELTA-S... (More)
- Ligand exchange on square-planar Pt(1,4-dithiane)2(2+), Pd(1,4-dithiane)2(2+), and Pt(Me2S)4(2+) has been studied as a function of temperature and pressure by H-1 NMR line-broadening, isotopic labeling, and magnetization transfer experiments with deuteriated nitromethane as solvent. Second-order rate constants and activation parameters are as follows: for 1,4-dithiane exchange on Pt(1,4-dithiane)2(2+), k2(298) = 28.8 +/- 4.8 m-1 s-1, DELTA-H double-ended dagger = 32.9 +/- 3.6 kJ mol-1, DELTA-S double-ended dagger = -106 +/- 11 J K-1 mol-1, and DELTA-V double-ended dagger = -12.6 +/- 1.1 cm3 mol-1; for 1,4-dithiane exchange on Pd(1,4-dithiane)2(2+), k2(298) = 9780 +/- 300 m-1 s-1, DELTA-H double-ended dagger = 22.9 +/- 0.6 kJ mol-1, DELTA-S double-ended dagger = -91.6 +/- 2.1 J K-1 mol-1, and DELTA-V double-ended dagger = -9.8 +/- 0.4 cm3 mol-1; for Me2S exchange on Pt(Me2S)4(2+), k2(298) = 1.54 +/- 0.07 m-1 s-1, DELTA-H double-ended dagger = 42.1 +/- 0.7 kJ mol-1, DELTA-S double-ended dagger = -100.2 +/- 2.2 J K-1 mol-1, and DELTA-V double-ended dagger = -22.0 +/- 1.3 cm3 mol-1. Second-order kinetics and negative entropies and volumes of activation indicate associative, I(a) or A, exchange mechanisms. For both metal centers, exchange of the chelated and strongly bound 1,4-dithiane, corrected for statistics, is faster than that of Me2S, probably due to steric factors. The ratio in reactivity for Pd/Pt is only ca. 1300 for Me2S and 340 for 1,4-dithiane, indicating a more pronounced sensitivity of Pt(II) to the electronic properties of the coordinated and entering ligands. Accordingly, activation volumes are more negative in the case of platinum. DELTA-V double-ended dagger for the Me2S exchange on Pt(II) is the most negative one reported so far for a square-planar solvent exchange. (Less)
- Abstract (Swedish)
- Ligand exchange on square-planar Pt(1,4-dithiane)2(2+), Pd(1,4-dithiane)2(2+), and Pt(Me2S)4(2+) has been studied as a function of temperature and pressure by H-1 NMR line-broadening, isotopic labeling, and magnetization transfer experiments with deuteriated nitromethane as solvent. Second-order rate constants and activation parameters are as follows: for 1,4-dithiane exchange on Pt(1,4-dithiane)2(2+), k2(298) = 28.8 +/- 4.8 m-1 s-1, DELTA-H double-ended dagger = 32.9 +/- 3.6 kJ mol-1, DELTA-S double-ended dagger = -106 +/- 11 J K-1 mol-1, and DELTA-V double-ended dagger = -12.6 +/- 1.1 cm3 mol-1; for 1,4-dithiane exchange on Pd(1,4-dithiane)2(2+), k2(298) = 9780 +/- 300 m-1 s-1, DELTA-H double-ended dagger = 22.9 +/- 0.6 kJ mol-1, DELTA-S... (More)
- Ligand exchange on square-planar Pt(1,4-dithiane)2(2+), Pd(1,4-dithiane)2(2+), and Pt(Me2S)4(2+) has been studied as a function of temperature and pressure by H-1 NMR line-broadening, isotopic labeling, and magnetization transfer experiments with deuteriated nitromethane as solvent. Second-order rate constants and activation parameters are as follows: for 1,4-dithiane exchange on Pt(1,4-dithiane)2(2+), k2(298) = 28.8 +/- 4.8 m-1 s-1, DELTA-H double-ended dagger = 32.9 +/- 3.6 kJ mol-1, DELTA-S double-ended dagger = -106 +/- 11 J K-1 mol-1, and DELTA-V double-ended dagger = -12.6 +/- 1.1 cm3 mol-1; for 1,4-dithiane exchange on Pd(1,4-dithiane)2(2+), k2(298) = 9780 +/- 300 m-1 s-1, DELTA-H double-ended dagger = 22.9 +/- 0.6 kJ mol-1, DELTA-S double-ended dagger = -91.6 +/- 2.1 J K-1 mol-1, and DELTA-V double-ended dagger = -9.8 +/- 0.4 cm3 mol-1; for Me2S exchange on Pt(Me2S)4(2+), k2(298) = 1.54 +/- 0.07 m-1 s-1, DELTA-H double-ended dagger = 42.1 +/- 0.7 kJ mol-1, DELTA-S double-ended dagger = -100.2 +/- 2.2 J K-1 mol-1, and DELTA-V double-ended dagger = -22.0 +/- 1.3 cm3 mol-1. Second-order kinetics and negative entropies and volumes of activation indicate associative, I(a) or A, exchange mechanisms. For both metal centers, exchange of the chelated and strongly bound 1,4-dithiane, corrected for statistics, is faster than that of Me2S, probably due to steric factors. The ratio in reactivity for Pd/Pt is only ca. 1300 for Me2S and 340 for 1,4-dithiane, indicating a more pronounced sensitivity of Pt(II) to the electronic properties of the coordinated and entering ligands. Accordingly, activation volumes are more negative in the case of platinum. DELTA-V double-ended dagger for the Me2S exchange on Pt(II) is the most negative one reported so far for a square-planar solvent exchange. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/64ccc866-abd3-433b-b3f4-fdaa04cdc63a
- author
- Frey, Urban ; Elmroth, Sofi K.C. LU ; Moullet, B. ; Elding, Lars Ivar LU and Merbach, Andre E.
- organization
- publishing date
- 1991-12-25
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Platinum(II), Palladium(II), 1,4-dithiane, Tetrakis(dimethylsulfide, Ligand exchange, Proton NMR, Kinetics, Reaction mechanism
- in
- Inorganic Chemistry
- volume
- 30
- issue
- 26
- pages
- 5033 - 5037
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- scopus:0001169247
- ISSN
- 1520-510X
- DOI
- 10.1021/ic00026a034
- language
- English
- LU publication?
- yes
- id
- 64ccc866-abd3-433b-b3f4-fdaa04cdc63a
- date added to LUP
- 2017-01-08 19:15:50
- date last changed
- 2021-01-03 04:36:55
@article{64ccc866-abd3-433b-b3f4-fdaa04cdc63a, abstract = {{Ligand exchange on square-planar Pt(1,4-dithiane)2(2+), Pd(1,4-dithiane)2(2+), and Pt(Me2S)4(2+) has been studied as a function of temperature and pressure by H-1 NMR line-broadening, isotopic labeling, and magnetization transfer experiments with deuteriated nitromethane as solvent. Second-order rate constants and activation parameters are as follows: for 1,4-dithiane exchange on Pt(1,4-dithiane)2(2+), k2(298) = 28.8 +/- 4.8 m-1 s-1, DELTA-H double-ended dagger = 32.9 +/- 3.6 kJ mol-1, DELTA-S double-ended dagger = -106 +/- 11 J K-1 mol-1, and DELTA-V double-ended dagger = -12.6 +/- 1.1 cm3 mol-1; for 1,4-dithiane exchange on Pd(1,4-dithiane)2(2+), k2(298) = 9780 +/- 300 m-1 s-1, DELTA-H double-ended dagger = 22.9 +/- 0.6 kJ mol-1, DELTA-S double-ended dagger = -91.6 +/- 2.1 J K-1 mol-1, and DELTA-V double-ended dagger = -9.8 +/- 0.4 cm3 mol-1; for Me2S exchange on Pt(Me2S)4(2+), k2(298) = 1.54 +/- 0.07 m-1 s-1, DELTA-H double-ended dagger = 42.1 +/- 0.7 kJ mol-1, DELTA-S double-ended dagger = -100.2 +/- 2.2 J K-1 mol-1, and DELTA-V double-ended dagger = -22.0 +/- 1.3 cm3 mol-1. Second-order kinetics and negative entropies and volumes of activation indicate associative, I(a) or A, exchange mechanisms. For both metal centers, exchange of the chelated and strongly bound 1,4-dithiane, corrected for statistics, is faster than that of Me2S, probably due to steric factors. The ratio in reactivity for Pd/Pt is only ca. 1300 for Me2S and 340 for 1,4-dithiane, indicating a more pronounced sensitivity of Pt(II) to the electronic properties of the coordinated and entering ligands. Accordingly, activation volumes are more negative in the case of platinum. DELTA-V double-ended dagger for the Me2S exchange on Pt(II) is the most negative one reported so far for a square-planar solvent exchange.}}, author = {{Frey, Urban and Elmroth, Sofi K.C. and Moullet, B. and Elding, Lars Ivar and Merbach, Andre E.}}, issn = {{1520-510X}}, keywords = {{Platinum(II); Palladium(II); 1,4-dithiane; Tetrakis(dimethylsulfide; Ligand exchange; Proton NMR; Kinetics; Reaction mechanism}}, language = {{eng}}, month = {{12}}, number = {{26}}, pages = {{5033--5037}}, publisher = {{The American Chemical Society (ACS)}}, series = {{Inorganic Chemistry}}, title = {{Proton NMR Kinetic Study of Ligand Exchange on Bis(1,4-dithiane)platinum(II), Bis(1,4-dithiane)palladium(II) and Tetrakis(dimethylsulfide)platinum(II) : High Presssure NMR Kinetics 51}}, url = {{http://dx.doi.org/10.1021/ic00026a034}}, doi = {{10.1021/ic00026a034}}, volume = {{30}}, year = {{1991}}, }