Chen Yinyin, Cui Tianhua, Chen Hua, Li Zheng Xue, Fu Haiyan, Li Ruixiang
Key Laboratory of Green Chemistry & Technology, Ministry of Education College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China.
Dalton Trans. 2023 Sep 13;52(35):12368-12377. doi: 10.1039/d3dt01430d.
A new series of cationic ruthenium(II) complexes, [RuCl(PPh)(κ-NNN-L1)]Cl (1), [RuH(PPh)(κ-NNN-L2)]Cl (2), and [RuH(PPh)(κ-NNN-L3)]Cl (3), bearing a 2,6-bis (1-R-5-methyl-pyrazol-3-yl) pyridine ligand (L1: R = H, L2: R = CH--CF, L3: R = CH--OCH), were synthesized and characterized with NMR, HRMS, and single-crystal X-ray diffraction. Their catalytic application was investigated in the acceptorless dehydrogenation (AD) of primary alcohols. Complex 1 outperformed 2 and 3 in terms of the selectivity towards the aldehydes, and provided the aldehydes with a yield of up to 99%, with good functional group tolerance under mild conditions. In addition, the only by-product of the reaction was dihydrogen, which can be collected as clean energy, and the reaction meets the requirements of environment-friendly chemistry. Complex 1 also proved to be a promising catalyst in the sequential AD/condensation reaction between the primary and secondary alcohols, affording α,β-unsaturated ketones in moderate to good selectivity.
一系列新型阳离子钌（II）配合物，即[RuCl(PPh)(κ-NNN-L1)]Cl（1）、[RuH(PPh)(κ-NNN-L2)]Cl（2）和[RuH(PPh)(κ-NNN-L3)]Cl（3）被合成出来，它们带有2,6-双（1-R-5-甲基-吡唑-3-基）吡啶配体（L1：R = H，L2：R = CH--CF，L3：R = CH--OCH），并通过核磁共振（NMR）、高分辨质谱（HRMS）和单晶X射线衍射进行了表征。研究了它们在伯醇的无受体脱氢反应（AD）中的催化应用。配合物1在对醛的选择性方面优于2和3，在温和条件下能以高达99%的产率得到醛，且具有良好的官能团耐受性。此外，该反应唯一的副产物是氢气，可作为清洁能源收集，该反应符合环境友好化学的要求。配合物1在伯醇和仲醇之间的连续AD/缩合反应中也被证明是一种有前景的催化剂，能以中等至良好的选择性得到α,β-不饱和酮。
