JOURNAL OF ORGANIC CHEMISTRY
·
2020
·
IF 4.335
Nian Zheng,Ce Liu,Ya-Nan Ding,Wei-Yu Shi,Bo-Sheng Zhang,Yong-Min Liang
Copper-catalyzed three-component redox-neutral ring opening of benzothiazoles with aryl iodides and O-benzoyl hydroxylamines for the synthesis of 1-amino-N-(2-(phenylthio)phenyl)methanimine has been developed. This one-pot reaction undergoes C–S and N–O bond cleavage and new C–S and C–N bond construction. Several control experiments excluded a free radical procedure and also demonstrated the secondary amine as a possible intermediate, which was vital to the catalytic reaction. Meanwhile, the deuteration experiment got rid of the C–H activation dehydroisomerization of the benzothiazole mechanism.
研究领域:
有机化学
·
合成化学
✓ 已验证
DOI
PubMed
高影响因子
ChemCatChem
·
2016
·Vol. 8
·期 11
·1929-1936
·
IF 4.724
Bin Chen,Bin Zhang,Yibo Zhang,Xiangguang Yang
Graphical Save it for a Raney day : A series of Ag-modified Ni catalysts is prepared, and the role of bimetallic effects on the selective cleavage of C−O and C−C bonds is investigated in glycerol hydrogenolysis, a model reaction for the utilization of biomass-derived polyols. Compared to Raney Ni, the optimal Raney Ni 6 Ag catalyst is more active in glycerol conversion and efficient for C−O bond cleavage to afford a higher selectivity toward C 3 products. A series of Ag-modified Ni catalysts was prepared, and the role of bimetallic effects on the selective cleavage of C−O and C−C bonds was investigated in glycerol hydrogenolysis, a model reaction for the utilization of biomass-derived polyols. Compared to Raney Ni, the optimal Raney Ni 6 Ag catalyst was more active in glycerol conversion and efficient for C−O bond cleavage to afford a higher selectivity toward C 3 products (1,2-propanediol and lactic acid; 88 %) at the same ∼70 % conversion of glycerol, especially 1,2-propanediol (73 %). On Ni catalysts, the hydrogenation of adsorbed species was the most likely rate-limiting step in glycerol hydrogenolysis under alkaline conditions. The Ag additive enhanced the hydrogenation ability of Ni catalysts, which should be related to the higher strength of the adsorption of hydrogen and the lower strength of the adsorption of substrates on Ni sites because of the formation of Ni-Ag alloys. A mechanistic interpretation was presented for the excellent catalytic behavior.
研究领域:
催化化学
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生物质利用
·
材料科学
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2024
·Vol. 14
·期 14
·4058-4067
·
IF 4.4
Yang You,Aijie Xu,Yao Lv,Lide Yang,Xuan Tang,Jie Tang,Yanglong Guo,Yao Cui,Wangcheng Zhan,Li Wang,Yun Guo,Sheng Dai
Complete oxidation of propane has drawn great attention in the fields of automotive emission control and volatile organic compound elimination. However, it is challenging to achieve high activity of this reaction due to the stability of propane. We here utilize a facile solvothermal method to construct tri-coordinated Al (AlIII) sites on the as-synthesized ST-Al2O3 support to alter the properties of supported Pt species. It is demonstrated that AlIII sites facilitate the dispersion and electron enrichment of supported Pt sites. Thus, Pt/ST-Al2O3 exhibits a superior activity toward complete propane oxidation, showing a 6.7-fold improvement in the turnover frequency over commercial Pt/Al2O3 catalysts. Meanwhile, Pt/ST-Al2O3 possesses a distinct reaction route originating from its stronger C–H and C–C cleavage capability, while having excellent activity not only in complete propane oxidation but also in the complete oxidation of other alkanes (CH4, C2H6, and n-C4H10). In addition, the AlIII construction strategy is successfully extended to more cases, e.g., Pd/ST-Al2O3 with higher Pd dispersion and electron density. This work provides a promising strategy for the control of the oxide support for advanced design and synthesis of alkane oxidation catalysts.
研究领域:
催化化学
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环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2021
·Vol. 168
·期 1
·016504
·
IF 4.316
Haomin Jiang,Yujuan Cheng,Zhaohui Wang,Zhiqun Bai,Yang Tang,Yanzhi Sun,Pingyu Wan,Yongmei Chen
The cleavage of the linkage bonds among the C9 units in lignin molecules via selective oxidation method to obtain small-weight aromatic compounds is an important way to lignin valorisation. In this study, the cleavage pathways of bonds in a lignin model compound, GGE (guaiacylglycerol-β-guaiacyl ether), by the reactive oxygen species (ROS) in situ generated through electrochemical oxygen reduction reaction (ORR) in an aprotic ionic liquid ([BMIM]BF4) was investigated. The results indicated that when the main ROS was ·OOH, coniferyl alcohol, guaiacol and vanillin were detected as the degradation products which is supposed to be caused by β-O-4 bonds cleavage; Otherwise, when HO2− was the main ROS, coniferyl alcohol could not be detected and the degradation reaction is believed to be trigerred by Cα-Cβ bonds cleavage.
研究领域:
生物化学
·
环境科学
✓ 已验证
DOI
高影响因子
ACS Applied Polymer Materials
·
2025
·
IF 4.7
Xiangzhuo Han,Yingchao Zhang,Jinkai Wang,Zhanchen Cui,Zuosen Shi
Sulfonate oxime ester photoinitiators (PIs) based on a thioether-substituted 1,8-naphthalenedicarboximide backbone exhibit good absorption at the emission wavelengths of commonly used LED lamps (385, 395, and 405 nm). The presence of weak C–S and N–O bonds in the molecular structure enables them to be cleaved under light, which leads to the generation of free radicals and cations with efficient initiation properties. Electron paramagnetic resonance spectroscopy supports the mechanism of C–S bond cleavage to produce free radicals, and UV–visible real-time spectroscopy in the presence of Rhodamine B base supports the mechanism of N–O bond cleavage to produce acids. These compounds are high-performance photoinitiators without any other additives for the polymerization of double-bonded compounds and epoxides. They can be initiated at low concentrations when exposed to UV-LEDs. These photoinitiators provide important ideas for the design and synthesis of photoinitiators, which have great potential for application in the field of photopolymerization, especially in hybrid light-curing systems.
研究领域:
材料科学
·
光化学
·
聚合物科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2024
·
IF 5.8
Yang-Yang Xu,Xing Fan,Feng-Yun Ma,Hai-Xu Zou,Xian-Yong Wei
Directly converting lignite into arenes as commodity chemicals and drop-in fuels is a highly desirable target for researchers. However, this is severely limited by the presence of stable inter unit C-O linkages in lignite. Herein, a highly active catalyst, Co-MoS 2 , has been designed and prepared to be used for the selective catalytic cleavage of inter unit C-O bridged bonds (BBs) in the conversion of Naomaohu (NMH), a lignite, to yield arenes. Both catalytic hydrogenation conversion (CHC) and thermal dissolution (a non-catalytic process, named NCHC) of NMH were conducted using n-hexane as the solvent. The soluble fractions from the first stage of NCHC (SF NCHC-1 ) and CHC (SF CHC-1 ), as well as the second stage of NCHC (SF NCHC-2 ) and CHC (SF CHC-2 ) were obtained using the same solvent. After the first-stage catalytic treatment, the relative contents of arenes and alkanes in SF CHC-1 increased by 16.7 % and 9.3 %, respectively, compared to those in SF NCHC-1 , and the relative content of oxygen-containing compounds (OCCs), such as alcohols, phenols , esters, ketones , acids, and furans, decreased by 13.2 %. For the second-stage conversion, the relative contents of arenes and alkanes in SF CHC-2 were 53.5 % and 15.5 % higher than those in SF NCHC-2 , and the relative contents of OCCs was only 6.6 % in SF CHC-2 . The catalytic mechanisms of cleavage of C-O BBs and deoxygenation were proposed based on the CHC of model compounds and density functional theory (DFT) calculation. The adsorption of OCCs and the activation of released hydrogen radical (H·) by Co-MoS 2 , followed by H· addition to the carbon atom connected to oxygen in C-O BBs and oxygen-containing functional groups, are crucial for the cleavage of C-O BBs and formation of deoxygenated compounds, particularly arenes.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2018
·
IF 0
Yueqing Wang,Xiaohai Yang,Hongyan Zheng,Xianqing Li,Yulei Zhu,Yongwang Li
The mechanism for the formation of furfural by dehydration of d -fructose via selective carbon-carbon (C C) bond cleavage was investigated over beta zeolite (Hβ). Several different pore size zeolites were employed to determine the shape selectivity of fructose isomers. Zeolitic pore sizes that smaller than the kinetic diameter of cyclic fructose also produced yield furfural (∼22.5%), while the high yield (66.0%) of hydroxymethylfurfural (HMF) can be achieved over large pore zeolite (USY zeolite), which could accommodate the cyclic fructose. These results indicated that the furfural formation likely began with acyclic fructose. In situ 13 C NMR and GC MS studies, using labeled 13 C-1-fructose as substrate, suggested that the conversion of fructose to furfural involved with splitting of the C5-C6 bond. Furthermore, the C1 compound from the cleavage of C C bond was identified as formaldehyde, inferring that the selective scission of C C bond was ascribe to the retro-aldol reaction. Interestingly, in situ NMR studies implied that the acyclic fructose mainly derived from pyranose forms. In addition, compared with glucose, fructose directly converted to furfural at the higher yield and reaction rate.
研究领域:
催化化学
·
有机化学
✓ 已验证
产品关联
DOI
Nature Communications
·
2023
·Vol. 14
·期 1
·1-7
·
IF 16.6
Li Peihui,Hou Songjun,Wu Qingqing,Chen Yijian,Wang Boyu,Ren Haiyang,Wang Jinying,Zhai Zhaoyi,Yu Zhongbo,Lambert Colin J.,Jia Chuancheng,Guo Xuefeng
The transformation from one compound to another involves the breaking and formation of chemical bonds at the single-bond level, especially during catalytic reactions that are of great significance in broad fields such as energy conversion, environmental science, life science and chemical synthesis. The study of the reaction process at the single-bond limit is the key to understanding the catalytic reaction mechanism and further rationally designing catalysts. Here, we develop a method to monitor the catalytic process from the perspective of the single-bond energy using high-resolution scanning tunneling microscopy single-molecule junctions. Experimental and theoretical studies consistently reveal that the attack of a halogen atom on an Au atom can reduce the breaking energy of Au−S bonds, thereby accelerating the bond cleavage reaction and shortening the plateau length during the single-molecule junction breaking. Furthermore, the distinction in catalytic activity between different halogen atoms can be compared as well. This study establishes the intrinsic relationship among the reaction activation energy, the chemical bond breaking energy and the single-molecule junction breaking process, strengthening our mastery of catalytic reactions towards precise chemistry.
研究领域:
催化
·
化学物理
·
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2017
·
IF 6.844
Huifang Liu,Min Wang,Hongji Li,Nengchao Luo,Shutao Xu,Feng Wang
Catalytic oxidation of C C bond is a key technology to transform petroleum-based as well as sustainable biomass feedstock into more valuable oxygenates. We herein describe a convenient and useful oxidation strategy of converting ketones into carboxylic acids using homogeneous copper catalyst without additives and with O 2 as the terminal oxidant. A wide range of aryl and aliphatic ketones as well as β–O–4 lignin models were selectively oxidized to acids via C C bond cleavage. Mechanism studies by EPR and in situ NMR elucidate the principles of Cu/O 2 reactivity that involves C H bond and O 2 activation via a peroxide species. This provides an important foundation for expanding the scope of useful aerobic oxidation reactions using copper catalysts.
研究领域:
有机化学
·
催化化学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Chuhan Zhang,Yanchang Chu,Linying Fu,Qiuyue Wang,Rui Ma,Donghai Xu,Le Yang
Lignin, a renewable resource rich in aromatic ring structures in nature, is an ideal natural source to produce aromatic compounds and cycloparaffin. Herein, we prepare MOF-derived Ni–MoxC/C and Co–MoxC/C as catalysts for the depolymerization of lignin and dimeric model compounds. Diphenyl ether (DPE) with 4-O-5 bond, benzyl phenyl ether (BPE) with α-O-4, and phenethyl phenyl ether (PPE) with β-O-4 are chosen as dimeric model compounds. Overall, Ni–MoxC/C and Co–MoxC/C show distinguished different activity toward product distribution. Ni–MoxC/C facilitates both C–O bond cleavage and hydrogenation of the benzene ring, and the main products are ethyl cyclohexane and cyclohexanol for all three model compounds. In contrast, Co–MoxC/C only facilitates C–O bond cleavage and obtains phenol and ethylbenzene as products. Similarly, for the depolymerization of lignin, cycloparaffins are obtained on Ni–MoxC/C, while phenol, guaiacol, 2,6-dimethoxyphenol, and their respective derivatives are obtained on Co–MoxC/C.
研究领域:
化学工程
·
可再生资源利用
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Wubin Liao,Peng Liao,Zheng Wang,Chenggang Ci,Shiwei Xie
The dephosphorylation of N-containing phosphonates is crucial for mitigating their potential ecological risks and enabling phosphorus resource recovery. Here, we first show that the electrochlorination process outperforms other advanced oxidation methods in terms of conversion efficiency and rate constants for orthophosphate production. The high efficacy of electrochlorination process is primarily attributed to the generation of hypochlorous acid (HClO) under neutral pH conditions, as substantiated by a combination of speciation analysis, quantitative assessments, and quenching experiments. Furthermore, density functional theory (DFT) calculation and LC-MS measurements show that the degradation of nitrilotris-methylenephosphonic acid (NTMP) by HClO occurs spontaneously, with a preferential cleavage of the C P bond over the C N bond, thereby facilitating the efficiency of the dephosphorylation reaction. Altogether, our findings provide key insights into the role of reactive chlorine species in the degradation of N-containing phosphonates, offering valuable evidence for the development of next-generation, more effective phosphorus recovery strategies.
研究领域:
环境科学
·
化学工程
·
计算化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Song Han,Yun Zhao,Mina Liang,Jinshui Su,Xiangxiong Zhai,Qi Zhang,Guoling Li,Zhonghai Ni
The photocatalytic cleavage of C α -C β bonds in lignin holds considerable potential for the production of value-added chemicals. Lignin consists of phenylpropane units interconnected by a variety of complex chemical bonds. Specifically, C-O bonds are more prevalent and relatively easier to cleave, whereas C–C bonds exhibit higher bond energy, rendering them more difficult to cleavage under conventional conditions. This study presents a phosphotungstic acid/phosphoric acid-functionalized porous tubular C 3 N 4 composite photocatalyst (PW/P-TCN). H 3 PO 4 modified PW/P-TCN surfaces enhance O 2 adsorption, improve separation and transfer of photogenerated carriers, and increase exposure of active sites. This promotes reactant adsorption and significantly boosts photocatalytic efficiency. Through this strategy, 1,2-diphenylethanol (DPol), used as a typical model substrate, is fully converted into aromatic monomers, achieving a DPol conversion rate of 99.9 %. Mechanistic studies reveal that C α -C β bond cleavage primarily involves the photo-oxidation mechanism mediated by electron-hole coupling. The construction of the PW/P-TCN heterojunction is essential for simultaneously sustaining robust reduction and oxidation capabilities. Natural lignin samples are applied to the photocatalytic system, and successful C–C bond cleavage depolymerization is achieved under optimal reaction conditions. This study offers valuable insights for the design of more economical and efficient photocatalysts for lignin depolymerization.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）