A mechanistic study of transfer hydrogenation catalyzed by cyclometallated ruthenium half-sandwich complexes
作者:Noor U. Din Reshi、Dineshchakravarthy Senthurpandi、Ashoka G. Samuelson
DOI:10.1016/j.jorganchem.2018.04.028
日期:2018.7
Transfer hydrogenation of aromatic ketones catalyzed by eight cyclometallated ruthenium half-sandwich complexes, including three new complexes, was examined. The catalytic process was studied using different ratios of substrate to base and base to catalyst and using a deuterated reductant. Optimum conditions for catalysis were shown to be in the presence of higher amounts of base in refluxing isopropanol
Cyclometallation of arylimines and nitrogen-containing heterocycles via room-temperature C–H bond activation with arene ruthenium(ii) acetate complexes
作者:Bin Li、Thierry Roisnel、Christophe Darcel、Pierre H. Dixneuf
DOI:10.1039/c2dt31401k
日期:——
methanol at room temperature produces stable (N^C)-cyclometallated ruthenium(II) complexesvia C–H bond activation/deprotonation. This method can be applied also to nitrogen-containing molecules: N-phenylpyrazole, 2-phenyl-2-oxazoline and benzo[h]quinoline. N-Phenyl-pyrazole, [RuCl2(p-cymene)]2 and diphenylacetylene directly lead to alkyneinsertion into the metallacycle C–Ru bond.
Ruthenium(ii) catalysed synthesis of unsaturated oxazolines via arene C–H bond alkenylation
作者:Bin Li、Karthik Devaraj、Christophe Darcel、Pierre H. Dixneuf
DOI:10.1039/c2gc36111f
日期:——
Monoalkenylation of arene CâH bonds directed by an oxazoline group to afford bifunctional alkenes is described using [RuCl2(p-cymene)]2 as the catalyst in the presence of 1,1â²-binaphthyl-2,2â²-diyl hydrogenphosphate (BNPAH) and of Cu(OAc)2·H2O under air. This reaction takes place under mild conditions in ethanol at 80 °C and tolerates the oxazoline function.
Autocatalytic Intermolecular versus Intramolecular Deprotonation in CH Bond Activation of Functionalized Arenes by Ruthenium(II) or Palladium(II) Complexes
作者:Indira Fabre、Niklas von Wolff、Gaëtan Le Duc、Emmanuel Ferrer Flegeau、Christian Bruneau、Pierre H. Dixneuf、Anny Jutand
DOI:10.1002/chem.201203813
日期:2013.6.3
zole (at RT). The accelerating effect of added acetate ions reveals an intermolecular deprotonation after CH bondactivation by a cationic RuII center (SE3 mechanism). The reactions of 1‐phenylpyrazole and 2‐phenyl‐2‐oxazoline first lead to the neutral cyclometalated complexes A2 and A3 ligated by one acetate. The latter dissociate to the cationic complexes B2+ and B3+, respectively, and acetate.
的C的活化 -1-苯基吡唑(的H键2)和2-苯基-2-恶唑啉(3通过)的[Ru(OAc)2(p -cymene)]是通过共产物的HOAc催化的自催化过程。在乙酸和水的存在下,反应的确确实更快,但是在碱K 2 CO 3的存在下,反应的确慢。在没有添加剂的情况下建立了反应顺序:2-苯基吡啶> 2-苯基-2-恶唑啉> 1-苯基吡唑(在室温下)。加入乙酸离子的加速作用揭示℃后的分子间去质子化通过阳离子钌H键活化II中心(S Ë3机制)。1-苯基吡唑和2-苯基-2-恶唑啉的反应首先导致由一种乙酸酯连接的中性环金属化配合物A 2和A 3。后者分别离解为阳离子络合物B 2 +和B 3 +和乙酸盐。一个或两个d原子的缓慢掺入2,3和2-苯基吡啶(1氘代乙酸的存在下观察到)。CH键活化/去质子化的“可逆性”是从阳离子络合物B n +(n= 1–3)。他们还参与了PhI的氧化添加,这决定了速率,并导致在