Kinetic Studies on the Terminal Pyridine Exchange Reactions of Some Oxo-Acetate Bridged Trinuclear Ruthenium Complexes. Influence of the Metal Oxidation State and Non-Leaving Terminal Ligand (CO).
Kinetic Studies on the Terminal Pyridine Exchange Reactions of Some Oxo-Acetate Bridged Trinuclear Ruthenium Complexes. Influence of the Metal Oxidation State and Non-Leaving Terminal Ligand (CO).
复制标题
一些氧代乙酸桥联三核钌配合物末端吡啶交换反应的动力学研究。
DOI：
10.1246/bcsj.65.1411
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发表时间：
1992
影响因子：
4
通讯作者：
Tasuku Ito
中科院分区：
文献类型：
--
作者：
M. Abe;Y. Sasaki;A. Nagasawa;Tasuku Ito
py-d5对三种三钌配合物[Ru 3（μ3-O）]末端吡啶的取代反应（μ-CH3COO）6（py）3]+（1）（Ru3（III，III，III）），Ru3（μ3-O）通过跟踪~ 1H NMR谱的变化，研究了（μ-CH_3COO）_6（py）_3（2）（Ru_3（II，III，III））和Ru_3（μ_3-O）（μ-CH_3COO）_6（CO）（py）_2（3）（Ru_3（II，III，III））在CD_3CN中的结构.速率实际上与[py-d5]（0.05-1.0 mol dm−3）无关。一级速率常数在55 °C时为3 × 10−5 s−1（ΔH = 123 ± 6 kJ mol−1，ΔS = +41 ± 19 J K−1 mol−1），50 °C时为5.9 × 10−4 s−1（ΔH = 122 ± 14 kJ mol−1，ΔS = +69 ± 44 J K−1 mol−1），55 °C时3 × 10−5 s−1（ΔH = 126 ± 9 kJ mol−1，ΔS = +52 ± 27 J K−1 mol−1）。速率常数似乎取决于金属中心的表观氧化态。虽然2中的三个Ru离子是等价的并且每个离子具有平均氧化数+2（2/3），但是3中具有配位py的Ru离子处于+3氧化态，因为+2氧化态位于羰基-Ru离子处。一个分离的机器人...
Substitution reactions of py-d5 for the terminal pyridines of the three triruthenium complexes, [Ru3(μ3-O)(μ-CH3COO)6(py)3]+ (1) (Ru3(III, III, III)), Ru3(μ3-O)(μ-CH3COO)6(py)3 (2) (Ru3(II, III, III)), and Ru3(μ3-O)(μ-CH3COO)6(CO)(py)2 (3) (Ru3(II, III, III)), have been studied in CD3CN by following the change in 1H NMR spectra. The rates are practically independent of [py-d5] (0.05–1.0 mol dm−3). The first-order rate constants are 3 × 10−5 s−1 at 55 °C (ΔH≠ = 123 ± 6 kJ mol−1, ΔS≠ = +41 ± 19 J K−1 mol−1), 5.9 × 10−4 s−1 at 50 °C (ΔH≠ = 122 ± 14 kJ mol−1, ΔS≠ = +69 ± 44 J K−1 mol−1), and 3 × 10−5 s−1 at 55 °C (ΔH≠ = 126 ± 9 kJ mol−1, ΔS≠ = +52 ± 27 J K−1 mol−1) for 1, 2, and 3, respectively. Rate constants appear to depend on the apparent oxidation state of the metal center. While the three Ru ions in 2 are equivalent and each ion has average oxidation number +2(2/3), Ru ions with coordinated py in 3 are in +3 oxidation state as the +2 oxidation state is localized at carbonyl-Ru ion. A dissociative mechan...