Table 4. Activation Parameters (ΔH‡, ΔS‡, ΔG‡) for the isomerization of [cis-MCl4(NO)(Hind)]− (M = Ru (1), Os(3)) and [trans-MCl4(NO)(Hind)]− (M = Ru (2), Os(4)) in C2D2Cl4a.
| ΔH‡ (kJ/mol) |
ΔS‡ (J/(mol·K)) |
ΔG‡(25 °C) (kJ/mol) | ΔG‡(110 °C) (kJ/mol) | ||||
|---|---|---|---|---|---|---|---|
| compound | process | method I | method II | method I | method II | method I | method I |
| [cis-RuCl4(NO)(Hind)]− (1) | cis → trans | 124.1 ± 0.3 | 122.8 ± 1.3 | –14.9 ± 0.7 | –18.7 ± 3.6 | 128.5 | 129.8 |
| [trans-RuCl4(NO)(Hind)]− (2) | trans → cis | 143.7 ± 0.5 | 138.8 ± 1.0 | 28.5 ± 1.4 | 31.0 ± 2.7 | 135.2 | 132.8 |
| [cis-OsCl4(NO)(Hind)]− (3) | cis → transb | 200.7 ± 0.7 | 142.7 ± 8.9 | 161.7 | 146.0 | ||
| [trans-OsCl4(NO)(Hind)]− (4) | trans → cis | 168.2 ± 0.6 | 85.4 ± 3.9 | 144.9 | 135.5 | ||
a
Estimation from method I by fitting k1 and k–1 by Eyring equation (eq 5) and by method II, simultaneously fitting the all population ratios at different temperatures via eqs 3 and 4 with constraining eq 5.
b
The kinetic parameters were obtained from reversible first order law analysis of trans to cis conversion data of 4.