27536-89-6Relevant articles and documents
A novel and efficient N-doping carbon supported cobalt catalyst derived from the fermentation broth solid waste for the hydrogenation of ketones via Meerwein–Ponndorf–Verley reaction
Chen, Yuxin,He, Runxia,Liu, Quansheng,Yao, Xuefeng,Zhou, Huacong
, (2021/12/10)
Most of the non-noble metal catalysts used for the Meerwein–Ponndorf–Verley (MPV) reaction of carbonyl compounds rely on the additional alkaline additives during preparation to achieve high efficiency. To solve this problem, in this work, we prepared a novel N-doped carbon supported cobalt catalyst (Co@CN), in which the carriers were derived from the nitrogen-rich organic waste, i.e., oxytetracycline fermentation residue (OFR, obtained from oxytetracycline refining workshop). No additional nitrogen sources were used during preparation. The results showed that inherent nitrogen in OFR could provide N-containing basic sites, and formed Co-N structures via coordinating with cobalt. The Co-N sites together with the coexisting Co(0) cooperated to catalyze the conversion of ethyl levulinate (EL) to γ-valerolactone (GVL) by MPV reaction. Co(0) dominated the activation of H in isopropanol, while Co-N dominated the formation of the six-membered ring transition state.
MOF-derived Ru@ZIF-8 catalyst with the extremely low metal Ru loading for selective hydrogenolysis of C–O bonds in lignin model compounds under mild conditions
Cao, Jing-Pei,Jiang, Wei,Xie, Jin-Xuan,Zhang, Chuang,Zhang, Jian-Li,Zhao, Liang,Zhao, Xiao-Yan,Zhao, Yun-Peng,Zhu, Chen
, p. 488 - 496 (2022/02/07)
Lignin hydrogenolysis to produce chemicals and biofuels is a challenge due to the stable C–O ether bond structure. Metal–organic framework (MOF) materials with excellent structural and chemical versatility have received widespread attention. Herein, a highly dispersed Ru metal anchored in functionalised ZIF-8 was fabricated by a general host–guest and reduction strategy. The Ru@ZIF-8 catalyst with a high specific surface area could efficiently promote the C–O bond cleavage of a variety of lignin model compounds under mild conditions. Compared with previous studies, the extremely low metal Ru loading in the Ru@ZIF-8 catalyst achieved a relatively higher activity. The introduction of Ru metal not only improved the dispersion of Zn metal, but also enhanced the electron density on the Zn surface, suggesting a high catalytic performance. It was more conducive for the Ru@ZIF-8 catalyst to exhibit the C–O bond cleavage activity when in the presence of both H2 and isopropanol. An investigation of the mechanism revealed that the direct hydrogenolysis of benzyl phenyl ether was the main reaction pathway.
Rhodium-catalyzed anti-Markovnikov hydrosilylation of alkenes
Liu, Wei,Lu, Wenkui,Wu, Xiaoyu,Yang, Liqun,Zhang, Zhaoguo
supporting information, (2022/02/01)
Rh-catalyzed anti-Markovnikov hydrosilylation of terminal alkenes and tertiary silanes using readily-available PPh3 as the ligand was reported. This method facilitated the effective synthesis of alkylsilanes with a wide substrate scope and high
Reactive separation of β-bromoethylbenzene from α-β-bromoethylbenzene mixtures: a Zn2+-mediated radical polymerization mechanism
Deng, Tianyu,Tian, Jiaming,Yan, Binhang,Zhu, Junqiu
supporting information, p. 1219 - 1222 (2022/02/03)
A Zn2+-induced reactive separation method for the purification of β-bromoethylbenzene from α-β-bromoethylbenzene mixtures is discovered, where the selective decomposition of α-bromoethylbenzene follows a radical mechanism. Zn2+ facilitates the homolysis of the C-Br bond of halohydrocarbons with benzyl bromide, enabling the separation of the corresponding isomers with almost identical physical properties.
Fabricating nickel phyllosilicate-like nanosheets to prepare a defect-rich catalyst for the one-pot conversion of lignin into hydrocarbons under mild conditions
Cao, Meifang,Chen, Bo,He, Chengzhi,Ouyang, Xinping,Qian, Yong,Qiu, Xueqing
supporting information, p. 846 - 857 (2022/02/09)
The one-pot conversion of lignin biomass into high-grade hydrocarbon biofuels via catalytic hydrodeoxygenation (HDO) holds significant promise for renewable energy. A great challenge for this route involves developing efficient non-noble metal catalysts to obtain a high yield of hydrocarbons under relatively mild conditions. Herein, a high-performance catalyst has been prepared via the in situ reduction of Ni phyllosilicate-like nanosheets (Ni-PS) synthesized by a reduction-oxidation strategy at room temperature. The Ni-PS precursors are partly converted into Ni0 nanoparticles by in situ reduction and the rest remain as supports. The Si-containing supports are found to have strong interactions with the nickel species, hindering the aggregation of Ni0 particles and minimizing the Ni0 particle size. The catalyst contains abundant surface defects, weak Lewis acid sites and highly dispersed Ni0 particles. The catalyst exhibits excellent catalytic activity towards the depolymerization and HDO of the lignin model compound, 2-phenylethyl phenyl ether (PPE), and the enzymatic hydrolysis of lignin under mild conditions, with 98.3% cycloalkane yield for the HDO of PPE under 3 MPa H2 pressure at 160 °C and 40.4% hydrocarbon yield for that of lignin under 3 MPa H2 pressure at 240 °C, and its catalytic activity can compete with reported noble metal catalysts.
One-step conversion of lignin-derived alkylphenols to light arenes by co-breaking of C-O and C-C bonds
Di, Yali,Li, Guangyu,Li, Zhiqin,Liu, Weiwei,Qiu, Zegang,Ren, Xiaoxiong,Wang, Ying
supporting information, p. 2710 - 2721 (2022/02/21)
The conversion of lignin-derived alkylphenols to light arenes by a one-step reaction is still a challenge. A 'shortcut' route to transform alkylphenols via the co-breaking of C-O and C-C bonds is presented in this paper. The catalytic transformation of 4-ethylphenol in the presence of H2 was used to test the breaking of C-O and C-C bonds. It was found that the conversion of 4-ethylphenol was nearly 100%, and the main products were light arenes (benzene and toluene) and ethylbenzene under the catalysis of Cr2O3/Al2O3. The conversion of 4-ethylphenol and the selectivity of the products were significantly influenced by the reaction temperature. The selectivity for light arenes reached 55.7% and the selectivity for overall arenes was as high as 84.0% under suitable reaction conditions. Such results confirmed that the co-breaking of the C-O and C-C bonds of 4-ethylphenol on a single catalyst by one step was achieved with high efficiency. The adsorption configuration of the 4-ethylphenol molecule on the catalyst played an important role in the breaking of the C-O and C-C bonds. Two special adsorption configurations of 4-ethylphenol, including a parallel adsorption and a vertical adsorption, might exist in the reaction process, as revealed by DFT calculations. They were related to the breaking of C-O and C-C bonds, respectively. A path for the hydrogenation reaction of 4-ethylphenol on Cr2O3/Al2O3 was proposed. Furthermore, the co-breaking of the C-O and C-C bonds was also achieved in the hydrogenation reactions of several alkylphenols. This journal is
Au/Pt Bimetallic Nanoparticle Decorated Microparticle Hybrid Catalyst System for Heterogeneous Hydrogenation of Styrene
Dikmen, Zeynep,ünver, Hakan,Bütün, Vural
, p. 3656 - 3663 (2021/03/30)
Poly(methacryloyloxy quinoline) microparticles were synthesized and used as reducing and stabilizing agents to prepare Au/Pt bimetallic nanoparticle (NP) decorated microparticle (MP) hybrid catalyst systems. These newly reported hybrid catalyst systems were used for reduction of styrene into ethylbenzene. Gold precursor was essential to prepare bimetallic NPs due to its great interaction with PMAQ resulting in the reduction to AuNPs on the surface of PMAQ MPs. Pt is also contrubute to NP formation thanks to this superior interaction between Au and PMAQ MPs. The bimetallic nanoparticle contents on the PMAQ MPs were determined as Au0.85Pt0.15 via XRD analysis. Au and Pt amounts were also determined with ICP-MS analysis. Although the metal amount in the sample was quite low, the catalytic effect was remarkable for hybrid system. AuNP decorated MPs had no catalytic activity for the reduction of styrene. Thus, it is clear that Pt was the active part of hybrid catalyst system for this reaction. On the other hand, gold precursor had been determined as crucial for the simultaneous synthesis of bimetallic NP decorated MPs as well. Graphic Abstract: New microparticles decorated with bimetallic nanoparticles have been synthesized and used effectively as a catalyst systems in the hydrogenation of styrene. While it is reported in the literature that such particles have successful catalytic activity in various oxidations, our particles stand out with reducing activities, reusabilities and easy production/removal properties. [Figure not available: see fulltext.]
Chemoselective Hydrogenation of Olefins Using a Nanostructured Nickel Catalyst
Klarner, Mara,Bieger, Sandra,Drechsler, Markus,Kempe, Rhett
supporting information, p. 2157 - 2161 (2021/05/21)
The selective hydrogenation of functionalized olefins is of great importance in the chemical and pharmaceutical industry. Here, we report on a nanostructured nickel catalyst that enables the selective hydrogenation of purely aliphatic and functionalized olefins under mild conditions. The earth-abundant metal catalyst allows the selective hydrogenation of sterically protected olefins and further tolerates functional groups such as carbonyls, esters, ethers and nitriles. The characterization of our catalyst revealed the formation of surface oxidized metallic nickel nanoparticles stabilized by a N-doped carbon layer on the active carbon support.
CoPd Nanoalloys with Metal–Organic Framework as Template for Both N-Doped Carbon and Cobalt Precursor: Efficient and Robust Catalysts for Hydrogenation Reactions
Zhu, Jie,Xu, Deng,Ding, Lu-jia,Wang, Peng-cheng
, p. 2707 - 2716 (2021/01/21)
In this work, a series of metal–organic framework (MOF)-derived CoPd nanoalloys have been prepared. The nanocatalysts exhibited excellent activities in the hydrogenation of nitroarenes and alkenes in green solvent (ethanol/water) under mild conditions (H2 balloon, room temperature). Using ZIF-67 as template for both carbon matrix and cobalt precursor coating with a mesoporous SiO2 layer, the catalyst CoPd/NC@SiO2 was smoothly constructed. Catalytic results revealed a synergistic effect between Co and Pd components in the hydrogenation process due to the enhanced electron density. The mesoporous SiO2 shell effectively prevented the sintering of hollow carbon and metal NPs at high temperature, furnishing the well-dispersed nanoalloy catalysts and better catalytic performance. Moreover, the catalyst was durable and showed negligible activity decay in recycling and scale-up experiments, providing a mild and highly efficient way to access amines and arenes.
Ligand-enabled and magnesium-activated hydrogenation with earth-abundant cobalt catalysts
Han, Bo,Jiao, Hongmei,Ma, Haojie,Wang, Jijiang,Zhang, Miaomiao,Zhang, Yuqi
, p. 39934 - 39939 (2021/12/31)
Replacing expensive noble metals like Pt, Pd, Ir, Ru, and Rh with inexpensive earth-abundant metals like cobalt (Co) is attracting wider research interest in catalysis. Cobalt catalysts are now undergoing a renaissance in hydrogenation reactions. Herein, we describe a hydrogenation method for polycyclic aromatic hydrocarbons (PAHs) and olefins with a magnesium-activated earth-abundant Co catalyst. When diketimine was used as a ligand, simple and inexpensive metal salts of CoBr2in combination with magnesium showed high catalytic activity in the site-selective hydrogenation of challenging PAHs under mild conditions. Co-catalyzed hydrogenation enabled the reduction of two side aromatics of PAHs. A wide range of PAHs can be hydrogenated in a site-selective manner, which provides a cost-effective, clean, and selective strategy to prepare partially reduced polycyclic hydrocarbon motifs that are otherwise difficult to prepare by common methods. The use of well-defined diketimine-ligated Co complexes as precatalysts for selective hydrogenation of PAHs and olefins is also demonstrated.
