Transfer hydrogenation of acetophenone from formic acid/triethylamine mixtures catalysed by the Ikariya-Noyori complex [(mesitylene)RuCl(R,R)-(TsDPEN)] has been investigated using simultaneous high-resolution FlowNMR and FlowUV-Vis spectroscopies coupled with on-line sampling head-space mass spectrometry and chiral high-performance liquid chromatography using an integrated, fully automated recirculating flow setup. In line with previous observations, the combined results show a gradual switch from formic acid dehydrogenation to hydrogen transfer mediated by the same Ru-hydride complex, and point to a Ru-formate species as the major catalyst intermediate. Hydrogen bonding in the formic acid/triethylamine mixture emerges as a sensitive 1H NMR probe for the transfer hydrogenation activity of the system and can be used to locate optimum reaction conditions.

中文翻译：

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从多技术操作反应监测中，了解对映选择性甲酸驱动的双官能钌配合物对苯甲酸驱动的加氢反应过程中的催化剂形态和氢共演化。

使用同时高分辨率的FlowNMR和FlowUV-Vis光谱同时结合On-Os光谱研究了由Ikariya-Noyori配合物[（间三甲苯）RuCl（R，R）-（TsDPEN）]催化的甲酸/三乙胺混合物中苯乙酮的转移加氢反应。在线采样顶空质谱和手性高效液相色谱仪，采用集成的全自动循环流设置。与以前的观察结果一致，综合结果表明，由相同的钌-氢化物配合物介导的甲酸脱氢逐渐转变为氢转移，并指出钌甲酸酯是主要的催化剂中间体。