Ru(II) complexes bearing 2,6-bis(benzimidazole-2-yl)pyridine ligands: A new class of catalysts for efficient dehydrogenation of primary alcohols to carboxylic acids and H2 in the alcohol/CsOH system
作者:Zengjin Dai、Qi Luo、Xianggao Meng、Renjie Li、Jing Zhang、Tianyou Peng
DOI:10.1016/j.jorganchem.2016.11.038
日期:2017.2
Mono-cationic Ru(II)-complexes [Ru(L)X(CH3CN)2]⋅X 1∼4 (1, L = 2,6-bis(benzimidazol-2-yl) pyridine (L1), X = Cl; 2, L = L1, X = OTf; 3, L = 2-(N-benzyl-benzimidazole-2-yl)-6-(benzimidazole-2-yl)pyridine (L2), X = Cl; 4, L = 2,6-bis(N-benzyl-benzimidazole-2-yl)pyridine (L3), X = Cl) were prepared and fully characterized. The two acetonitrile ligands of each complex are coordinated to the metal center
单阳离子的Ru(II)-complexes的[Ru(大号)X(CH 3 CN)2 ]⋅X 1〜4(1,大号 = 2,6-双(苯并咪唑-2-基)吡啶(L1)中,X = Cl;2,L = L1,X = OTf;3,L = 2-(N-苄基-苯并咪唑-2-基)-6-(苯并咪唑-2-基)吡啶(L2),X = Cl;4制备了L = 2,6-双(N-苄基-苯并咪唑-2-基)吡啶(L3),X = Cl。每个络合物的两个乙腈配体与金属中心配位彼此顺式。配合物2在结构上也通过X射线晶体学表征。结果发现,复合体1〜4可以催化伯醇的脱氢acceptorless到相应的羧酸和H 2在碱性水溶液,和反应性如下顺序1 = 2 > 4 > 3。此外,复合物1或2可以有效地催化各种伯醇向羧酸的转化,产率高(72%–98%),并且在醇/ CsOH体系中具有高选择性(1/1,mol / mol)。在CsOH中使用