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81.
丙酸水相加氢反应中Ru负载量对C-C键断裂的影响 总被引:1,自引:1,他引:0
考察了(1.0、4.0、6.0 wt.%)Ru/ZrO2催化剂的丙酸水相加氢性能。采用N2物理吸附、CO脉冲化学吸附、H2程序升温还原(H2-TPR)、CO和丙酸吸附傅里叶变换红外光谱(FTIR)研究了Ru/ZrO2催化剂的物理化学性质。CO-FTIR表明,Ru负载量增加,催化剂表面Ru粒子的富电子程度增加,更接近金属Ru的本征特性。丙酸FTIR表明,丙酸分子在Ru/ZrO2催化剂表面经解离吸附主要形成丙酰基和丙酸盐物种。随Ru含量增加,丙酰基更容易发生脱羰反应,导致C-C键断裂。 相似文献
82.
A chiral catalyst, Cp*RhTsDPEN (Cp* = pentamethyl cyclopentadiene, TsDPEN = substitutive phenylsulfonyl-l,2-diphenylethylenediamine), was synthesized and immobilized at the surface of glass. The immobilized catalyst exhibited good catalytic efficiency for asymmetric transfer hydrogenation of aromatic ketones in water with HCOONa as hydrogen source. 相似文献
83.
84.
《催化学报》2014,(12):1781-1792
Chin. J. Catal., 2014, 35: 1911–1916 doi: 10.1016/S1872‐2067(14)60208‐4 Dehydrogenation of primary aliphatic alcohols to aldehydes over Cu‐Ni bimetallic catalysts Tianliang Lu, Zhongtian Du, Junxia Liu, Chen Chen, Jie Xu * Dalian Institute of Chemical Physics, Chinese Academy of Sciences; University of Chinese Academy of Sciences 相似文献
85.
Yang Lv Dr. Miaomiao Han Dr. Wanbing Gong Dongdong Wang Dr. Chun Chen Prof. Guozhong Wang Prof. Haimin Zhang Prof. Huijun Zhao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(52):23727-23732
Selective hydrogenation of C=O against the conjugated C=C in cinnamaldehyde (CAL) is indispensable to produce cinnamyl alcohol (COL). Nonetheless, it is challenged by the low selectivity and the need to use organic solvents. Herein, for the first time, we report the use of Fe-Co alloy nanoparticles (NPs) on N-doped carbon support as a selective hydrogenation catalyst to efficiently convert CAL to COL. The resultant catalyst with the optimized Fe/Co ratio of 0.5 can achieve an exceptional COL selectivity of 91.7 % at a CAL conversion of 95.1 % in pure water medium under mild reaction conditions, ranking it the best performed catalyst reported to date. The experimental results confirm that the COL selectivity and CAL conversion efficiency are, respectively promoted by the presence of Fe and Co, while the synergism of the alloyed Fe-Co is the key to concurrently achieve high COL selectivity and CAL conversion efficiency. 相似文献
86.
Dr. Andreas Lerchen Dr. Narasimhulu Gandhamsetty Elliot H. E. Farrar Dr. Nils Winter Dr. Johannes Platzek Dr. Matthew N. Grayson Prof. Dr. Varinder K. Aggarwal 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(51):23307-23311
(−)-Finerenone is a nonsteroidal mineralocorticoid receptor antagonist currently in phase III clinical trials for the treatment of chronic kidney disease in type 2 diabetes. It contains an unusual dihydronaphthyridine core. We report a 6-step synthesis of (−)-finerenone, which features an enantioselective partial transfer hydrogenation of a naphthyridine using a chiral phosphoric acid catalyst with a Hantzsch ester. The process is complicated by the fact that the naphthyridine exists as a mixture of two atropisomers that react at different rates and with different selectivities. The intrinsic kinetic resolution was converted into a kinetic dynamic resolution at elevated temperature, which enabled us to obtain (−)-finerenone in both high yield and high enantioselectivity. DFT calculations have revealed the origin of selectivity. 相似文献
87.
本文主要介绍了一系列基于二茂铁骨架的三齿配体:f-amphox、f-ampha、f-amphol和f-amphamide的合成及其应用。这四类手性膦氮配体的铱络合物可以高活性(TON高达1 000 000)、高转化率(>99%)、高对映选择性(>99% ee)地催化(官能团化)酮等底物的不对称氢化反应。该系列配体成功地应用于地诺帕明、苯福林和沙丁胺醇等手性医药中间体的不对称合成。与传统路线相比,这些合成方法更高效,副产物更少,“三废”排放量更低。 相似文献
88.
Oleg Parenago Alexey Rybaltovsky Evgeniy Epifanov Andrey Shubnyi Galina Bragina Alexey Lazhko Dmitry Khmelenin Vladimir Yusupov Nikita Minaev 《Molecules (Basel, Switzerland)》2020,25(24)
To obtain a supported heterogeneous catalyst, laser ablation of metallic palladium in supercritical carbon dioxide was performed in the presence of a carrier, microparticles of γ-alumina. The influence of the ablation process conditions—including supercritical fluid density, ablation, mixing time of the mixture, and laser wavelength—on the completeness and efficiency of the deposition of palladium particles on the surface of the carrier was studied. The obtained composites were investigated by scanning and transmission electron microscopy using energy dispersive spectroscopy. We found that palladium particles were nanosized and had a narrow size distribution (2–8 nm). The synthesized composites revealed high activity as catalysts in the liquid-phase hydrogenation of diphenylacetylene. 相似文献
89.
90.
Meera Mehta Jose M. Goicoechea 《Angewandte Chemie (International ed. in English)》2020,59(7):2715-2719
Molecular compounds featuring nitrogen atoms are typically regarded as Lewis bases and are extensively employed as donor ligands in coordination chemistry or as nucleophiles in organic chemistry. By contrast, electrophilic nitrogen‐containing compounds are much rarer. Nitrenium cations are a new family of nitrogen‐based Lewis acids, the reactivity of which remains largely unexplored. In this work, nitrenium ions are explored as catalysts in five organic transformations. These reactions are the first examples of Lewis acid catalysis employing nitrogen as the site of substrate activation. Moreover, these compounds are readily accessed from commercially available reagents and exhibit remarkable stability toward moisture, allowing for benchtop transformations without the need to pretreat solvents. 相似文献