单氢钌配合物与水和2,2,2-三氟乙醇的作用机理

利用原位¹H和³¹P NMR对单氢钌配合物TpRu(PPh₃)(CH₃CN)H Tp＝hydrotris(pyrazolyl)borate]与H₂O和酸性HOCH₂CF₃的反应进行了研究, 结果显示相应的反应产物分别是TpRu(PPh₃)(CH₃CN)(OH) 和TpRu(PPh₃)(CH₃CN)(OCH₂CF₃). 观察到反应过程中Ru—H…HOH和Ru—H…HOCH₂CF₃分子间的氢键作用. 提出了生成TpRu(PPh₃)(CH₃CN)(OH)和TpRu(PPh₃)(CH₃CN)(OCH₂CF₃)的不同作用机理. 在水存在下, TpRu(PPh₃)(CH₃CN)H 与H₂O反应, 经过中间体TpRu(PPh₃)(H₂O)H和TpRu(PPh₃)(OH)(η²-H₂)生成产物TpRu(PPh₃)(CH₃CN)(OH). 而TpRu(PPh₃)(CH₃CN)H与酸性HOCH₂CF₃反应时, 单氢配体被质子化形成中间体TpRu(PPh₃)(CH₃CN)- (η²-H₂)](OCH₂CF₃), 进而转变成产物TpRu(PPh₃)(CH₃CN)(OCH₂CF₃). TpRu(PPh₃)(CH₃CN)(OCH₂CF₃)与H₂作用, 经中间体TpRu(PPh₃)(HOCH₂CF₃)H生成TpRu(PPh₃)(η²-H₂)H.

Interaction Mechanisms of Ruthenium Hydride Complex with Water and 2,2,2-Trifluoroethanol

In situ ¹H and ³¹P NMR methods were used to study the reactions of ruthenium hydride complex TpRu(PPh₃)(CH₃CN)H Tp＝hydrotris(pyrazolyl)borate] with water and acidic HOCH₂CF₃. The result shows that the the products were TpRu(PPh₃)(CH₃CN)(OH) and TpRu(PPh₃)(CH₃CN)(OCH₂CF₃), respectively. The presence of Ru—H…HOH and Ru—H…HOCH₂CF₃ dihydrogen-bonding interactions was observed. The different mechanisms involving the formation of TpRu(PPh₃)(CH₃CN)(OH) and TpRu(PPh₃)(CH₃CN)(OCH₂CF₃) are proposed. In the presence of water, TpRu(PPh₃)(CH₃CN)H reacts with H₂O to produce TpRu(PPh₃)(CH₃CN)(OH) via the intermediates TpRu(PPh₃)(H₂O)H and TpRu(PPh₃)(OH)(η²-H₂). However, in the case of CF₃CH₂OH, the protonation of the hydride ligand by CF₃CH₂OH generates a key species TpRu(PPh₃)(CH₃CN)(η²-H₂)](OCH₂CF₃), which is then transformed to TpRu(PPh₃)(CH₃CN)(OCH₂CF₃). TpRu(PPh₃)(CH₃CN)(OCH₂CF₃) reacts with H₂ to result in the formation of TpRu(PPh₃)(η²-H₂)H via the intermediate TpRu(PPh₃)(HOCH₂CF₃)H