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11.
I. A. Opeida R. B. Sheparovych Yu. M. Hrynda O. Yu. Khavunko M. O. Kompanets A. N. Shendryk 《国际化学动力学杂志》2019,51(9):679-688
A kinetic study of the initiated oxidation of benzyl alcohol and cumene by molecular oxygen was performed. The oxidation rate was more enhanced with N-hydroxyphthalimide (NHPI) in the case of cumene than that of benzyl alcohol. HOOH inhibits cumene oxidation and does not affect the rate of oxidation of benzyl alcohol. It was shown that termination chain reactions of phthalimid-N-oxyl radicals (PINO•) does not occur with RОО• and proceeds with HOO•. A kinetic scheme of the process and an equation describing the kinetics of oxidation of benzyl alcohol in the presence of NHPI are proposed. Using the PM7 method, the thermodynamic characteristics of elementary steps of oxidation explaining the obtained results were calculated. 相似文献
12.
Ruirui Xu Kun Wang Haoying Liu Prof. Dr. Weijun Tang Dr. Huaming Sun Prof. Dr. Dong Xue Prof. Dr. Jianliang Xiao Prof. Dr. Chao Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(49):22143-22148
A ruthenium-catalyzed formal anti-Markovnikov hydroamination of allylic alcohols for the synthesis of chiral γ-amino alcohols is presented. Proceeding via an asymmetric hydrogen-borrowing process, the catalysis allows racemic secondary allylic alcohols to react with various amines, affording enantiomerically enriched chiral γ-amino alcohols with broad substrate scope and excellent enantioselectivities (68 examples, up to >99 % ee). 相似文献
13.
Victoria A. Ternes Hannah A. Morgan Austin P. Lanquist Michael J. Murray Bradley M. Wile 《应用有机金属化学》2020,34(4):e5459
Herein we report the preparation of a series of Ru(II) complexes featuring α-iminopyridine ligands bearing thioether functionality (NNSR, where R = Me, CH2Ph, Ph). Metallation using [(p-cymene)RuCl]2 permits access to Ru complexes with a κ2-N,N donor set in which the thioether moiety remains uncoordinated. In the presence of a strong field ligand such as acetonitrile or triphenylphosphine, the p-cymene moiety is displaced, and the ligand adopts a κ3-N,N,S binding mode. These complexes are characterized using a combination of solution and solid state methods, including the crystal structure of [(NNSMe)Ru (NCMe)2Cl]Cl. The κ2-N,N-Ru(II) complexes are shown to serve as efficient precatalysts for the oxidation of sec-phenethyl alcohol at modest loadings (alcohol: Ru = 20:1), using a variety of external oxidants and solvents. The complex bearing an S-Ph donor was found to be the most active oxidation catalyst of those surveyed, suggesting that the thioether donor plays an active role in the catalytic cycle. 相似文献
14.
以二芳基烯丙醇与溴乙腈为原料,开发了一种可见光诱导的合成δ-酮腈的方法.控制实验的结果表明,该反应可能是通过自由基机理进行的,溴乙腈作为氰甲基自由基源参与到反应中. 相似文献
15.
Yingjun Sun Dr. Yingjie Li Yingnan Qin Prof. Lei Wang Prof. Shaojun Guo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(18):4032-4038
Searching for new anti-poisoning Pt-based catalysts with enhanced activity for alcohol oxidation is the key in direct alcohol fuel cells (DAFCs). However, in the traditional strategy for designing bimetallic or multimetallic alloy is still difficult to achieve a satisfactory heterogeneous electrocatalyst because the activity often depends on only the surface atoms. Herein, we fabricate the multicomponent active sites by creating a sulfide structure on 1D PtNiCo trimetallic nanowires (NWs), to give a PtNiCo/NiCoS interface NWs (IFNWs). Owing to the presence of sulfide interfaces, the PtNiCo/NiCoS IFNWs enable an impressive methanol/ethanol oxidation reaction (MOR/EOR) performance and excellent anti-CO poisoning tolerance. They have the MOR and EOR mass activities of 2.25 Amg-1Pt and 1.62 Amg-1Pt, around 1.26, 3.21 and 1.46, 2.96 times higher than those of PtNiCo NWs and commercial Pt/C, respectively. CO-stripping and XPS measurements further demonstrate that the new interfacial structure and optimal bonding of Pt−CO can result in accelerating the removal of surface adsorbed carbonaceous intermediates. Moreover, such a unique structure has also demonstrated a much-improved ability for the electrochemical detection of some important molecules (H2O2 and NH2NH2). 相似文献
16.
Hui Li Jian Liu Juan Zhao Huiting He Dr. Dabo Jiang Prof. Steven Robert Kirk Prof. Qiong Xu Dr. Xianxiang Liu Prof. Dulin Yin 《ChemistryOpen》2021,10(4):477-485
A series of tetraimidazolium salts with different anions was prepared and applied in the isomerization of β-pinene oxide. After examining the activity of different catalysts, a remarkable enhancement of the selectivity of perillyl alcohol (47 %) was obtained over [PEimi][HNO3]4 under mild reaction conditions and using DMSO as the solvent. Furthermore, noncovalent interactions between solvent molecules and the catalyst were found by FT-IR spectroscopy and confirmed by computational chemistry. The homogeneous catalyst showed excellent stability and was reused up to six times without significant loss. 相似文献
17.
Surin Saipanya Li Fang Suwaphid Themsirimongkon Suphitsara Maturost Natthapong Pongpichayakul Napapha Promsawan Paralee Waenkaew 《先进技术聚合物》2023,34(1):120-133
The aim of this research was to study the efficiency of polyvinyl alcohol (PVA)-modified graphene oxide (GO) as a supporting material for catalysts that oxidize formic acid. The active metal catalysts (e.g., Pt and Pd) were electrodeposited on PVA/GO surfaces. The morphologies of the prepared catalysts were characterized by scanning electron microscopy and transmission electron microscopy, while their chemical compositions were identified by X-ray diffraction and X-ray photoelectron spectroscopy. The results show that compared with the other catalysts on GO, the prepared active PtPd alloy catalyst nanoparticles with 11.49–20.73 nm sizes were well dispersed on the PVA/GO surfaces. Electrochemical results indicate that the activities of the catalysts with PVA provided a higher current density than that of the catalysts without PVA. The bimetallic 3Pt3Pd/PVA/GO catalyst showed the greatest catalytic activity, stability, and CO oxidation when compared to those of other catalysts. The electronic, morphological, and structural properties promote the mass-charge transfer through the interaction. These results indicate that the PVA-modified GO provides a suitable site for active bimetallic catalyst surfaces, resulting in excellent formic acid oxidation and high CO elimination. The 3Pt3Pd/PVA/GO electrocatalyst is promising for enhancing formic acid oxidation. 相似文献
18.
Jan Eric Neuburger Alina Gazizova Sven Tiedemann Prof. Dr. Jan von Langermann 《European journal of organic chemistry》2023,26(34):e202201471
This study highlights the straight-forward synthesis of substituted 1,2-amino alcohols from simple and readily available aromatic methyl ketones. Starting from acetophenone derivatives, the straight-forward synthesis strategy involved an initial bromination of the alpha-positioned methyl group in the first step, followed by a simple hydrolysis to the hydroxyketone (2-hydroxyacetophenone). The hydroxylated intermediate was subsequently converted from Silicibacter pomeroyi to the final 1,2-amino alcohol by using the transaminase. The transaminase-catalyzed reaction proceeded with yields up to 62 % and always excellent enantiomeric excess of >99 %. Interestingly, the keto-enol-tautomerism of the hydroxyl ketone yields an unexpected amino alcohol isomer. 相似文献
19.
Dr. Martin Kamlar Dr. Ivana Císařová Prof. Jan Veselý 《European journal of organic chemistry》2023,26(32):e202300400
We report a Brønsted acid-catalyzed synthesis of tetrasubstituted allenyl compounds decorated with heterocyclic sulfenyl group. The reaction proceeds readily from available propargylic alcohols in the presence of pentacarboxycyclopenatadienes (PCCPs) as organocatalysts. The developed strategy provides tetrasubstituted allene derivatives in high yields (from 55 to 98 %) and under mild reaction conditions. 相似文献
20.
Andreia S. Oliveira João C. Silva Mónica V. Loureiro Ana C. Marques Nicholas A. Kotov Rogério Colaço Ana P. Serro 《Macromolecular bioscience》2023,23(2):2200240
Cartilage replacement materials exhibiting a set of demanding properties such as high water content, high mechanical stiffness, low friction, and excellent biocompatibility are quite difficult to achieve. Here, poly(p-phenylene-2,6-benzobisoxazole) (PBO) nanofibers are combined with polyvinyl alcohol (PVA) to form a super-strong structure with a performance that surpasses the vast majority of previously existing hydrogels. PVA–PBO composites with water contents in the 59–76% range exhibit tensile and compressive moduli reaching 20.3 and 4.5 MPa, respectively, and a coefficient of friction below 0.08. Further, they are biocompatible and support the viability of chondrocytes for 1 week, with significant improvements in cell adhesion, proliferation, and differentiation compared to PVA. The new composites can be safely sterilized by steam heat or gamma radiation without compromising their integrity and overall performance. In addition, they show potential to be used as local delivery platforms for anti-inflammatory drugs. These attractive features make PVA–PBO composites highly competitive engineered materials with remarkable potential for use in the design of load-bearing tissues. Complementary work has also revealed that these composites will be interesting alternatives in other industrial fields where high thermal and mechanical resistance are essential requirements, or which can take advantage of the pH responsiveness functionality. 相似文献