Dimeric pincer-type ruthenium(II)-NNN complexes bearing an unsymmetrical pyrazolyl-pyridylamino-pyridine ligand were prepared and characterized by NMR, elemental analysis, and X-ray single crystal structural determination. These complexes exhibited very high catalytic activity for both transfer hydrogenation of ketones and acceptorless dehydrogenation of secondary alcohols, achieving TOF values up to 1.9 × 10⁶ h^–1 in the transfer hydrogenation of ketones. The high catalytic activity of the Ru(II) complex catalysts is attributed to the presence of the unprotected NH functionality in the ligand and hemilabile unsymmetrical coordination environment around the central metal atoms in the complex.

中文翻译：

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带有吡唑基-吡啶基氨基-吡啶配体的二聚钌（II）-NNN复合催化剂，用于酮的转移加氢和醇的无受体脱氢

制备了带有不对称吡唑基-吡啶基氨基-吡啶配体的二聚钳型钌（II）-NNN配合物，并通过NMR，元素分析和X射线单晶结构测定进行了表征。这些配合物对酮的转移氢化和仲醇的无受体脱氢均显示出非常高的催化活性，在酮的转移氢化中，TOF值高达1.9×10 ⁶ h ^–1。Ru（II）配合物催化剂的高催化活性归因于配体中未保护的NH官能团的存在以及配合物中中心金属原子周围的半不稳定不对称配位环境。