Molecular Catalysis
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2020
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IF 3.687
Sihao Xu,Guojun Shi,Ya Feng,Chong Chen,Lijun Ji
Acetophenone is an important industrial intermediate and generally produced by the Friedel-Crafts acylation reaction, suffering from a low reactivity and serious equipment corrosion. Direct oxidation of ethylbenzene to acetophenone by molecular oxygen will be benign and cost-effective. The catalytic performance of NHPI/Co(II) herein was investigated by selective oxidation of ethylbenzene to acetophenone in different solvents at room temperature. The solvent hexafluoropropan-2-ol (HFIP) was found to markedly enhance the transformation efficiency from ethylbenzene to acetophenone in comparison with acetic acid, pyridine and ethanol, and the ethylbenzene conversion and the selectivity to acetophenone was high up to 87.9 % and 61.2 %, respectively. A higher concentration of phthalimide -N- oxyl (PINO) radicals was observed by an in situ electron paramagnetic resonance spectrometer (EPR) in HFIP with respect to other solvents, suggesting that HFIP may facilitate the generation of the N-oxyl radical and thus promote the selective oxidation of ethylbenzene to acetophenone. Furthermore, the benzylic carbon radical (PhCHCH 3 ) from ethylbenzene was trapped by tetramethylpiperidine N-oxyl radical (TEMPO) and observed by a high resolution mass spectrometer. The findings of both PINO and PhCHCH 3 under reaction conditions indicated that the selective oxidation of ethylbenzene to acetophenone catalyzed by NHPI/Co(II) should proceed via a radical mode. The selective oxidation of ethylbenzene to acetophenone using molecular oxygen by NHPI/Co(II) in HFIP exhibited an important industrial application prospect.
研究领域:
化学工程
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有机化学
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DOI
高影响因子
Molecular Catalysis
·
2025
·
IF 4.9
Nana wang,Jiayu Teng,Yanmei Dai,Zijuan Tao,Changshun Huang,Liangli Luo,Zhimin Ou
To enhance the catalytic efficacy of nitroreductase and optimize the utilization of m-nitroacetophenone substrate, a novel nitroreductase, EcNTR, was isolated from Enterobacter cloacae ZJUT16 (CGMCC NO:28,310). The gene encoding EcNTR was successfully cloned and heterologously expressed. Through alanine scanning and site-saturation mutagenesis, two mutants, EcNTR-G20N/I54N and EcNTR-G20N/Y154D, were identified, exhibiting 5.01-fold and 4.69-fold higher specific activities, respectively, compared to wild-type EcNTR. At a substrate concentration of 80 mM, these mutants achieved a conversion rate of 98.52 %. Further optimization of the whole-cell catalytic conditions for mutant EcNTR-G20N/Y154D—specifically, a reaction time of 12 h, temperature of 30 °C, cell concentration of 100 g /L, use of DMSO as co-solvent, and 80 mM substrate—resulted in a yield of 99.2 %. These findings indicate that conformational changes in the active site region improved enzyme-substrate binding efficacy, thereby enhancing enzyme activity and catalytic ability. This study lays a foundation for the further development of nitroreductases for the efficient degradation of nitro-containing compounds.
研究领域:
生物化学
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酶工程
·
合成生物学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2017
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IF 6.216
Ke Lu,Kungang Chai,Qinghua Liang,Zhijun Xu,Guoyu Li,Hongbing Ji
A polysaccharide-based polymer (abbrev., SMP) was prepared via the crosslinking of starch with 4,4-methylene diphenyl diisocyanate and employed as an adsorbent for selective separation of acetophenone (AP) and 1-phenylethanol (PE) which coexist extensively in petrochemical by-products and effluents. The successful crosslinking was proved by FTIR and XPS, and the rough morphology as well as porous structure was also demonstrated in XRD, SEM and N 2 adsorption-desorption analysis. Using SMP as adsorbent, the adsorption kinetics and isotherms were both investigated in single-component system. Both kinetic and thermodynamic parameters of the adsorption process were obtained. Further thermodynamic investigation indicated that the adsorption was exothermic and spontaneous. Compared to the starch-based polymers whose frameworks contain no phenyl ring, SMP exhibits both higher selectivity and capacity for AP in the competitive adsorption. Additionally, increasing the level of crosslinking in SMP favors its adsorption performance. Furthermore, continuous adsorption-desorption indicated high separation ability and regeneration efficiency of SMP. Finally, the mechanism studies suggested that the adsorption mechanisms may be physisorption involving noncovalent interactions, permitting preference to AP over PE.
研究领域:
环境科学
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化学工程
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
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2014
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IF 3.679
Zhihua Chen,Wenqi Chen,Tianxia Tong,Aiwu Zeng
The continuous liquid phase Friedel–Crafts acylation of toluene (T) by acetic anhydride (AA) over HBEA zeolite was carried out in a fixed bed reactor, with acetic acid (AC) as a solvent. 4-Methylacetophenone (4-MAP) was selectively formed in the initial reaction stage. However, a rapid catalyst deactivation occurred with a sharp decrease of the conversion of acetic anhydride, and this was mainly caused by 4-MAP and heavy compounds (‘coke’) existing in the zeolite pore, which poisoned the active sites of the catalyst. The use of excess toluene and moderate acetic acid enhanced catalyst activity and stability to some extent as it limited both the retention of 4-MAP and the formation of ‘coke’. Moreover, a considerable reduction of Broensted acid sites after deactivation revealed that the toluene acylation is primarily a Broensted acid catalyzed reaction.
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2022
·
IF 7.392
Pengyun Zhang,Junjie Chen,Lixin Song,Ningxia Gu,Pingfan Du,Xiang Chen,Leying Zha,Wei-Hsiang Chen,Jie Xiong
As known, some defect states of perovskite film still seriously affect the efficiency and stability of perovskite solar cells (PSCs), and different passivation approaches have different passivation principles, areas, degrees and additional effects on perovskite films. Herein, in this contribution, we design a three-step optimization method including interface optimization and additive passivation strategies for enhancing the quality of perovskite films all-round, thereby increasing the power conversion efficiency (PCE) as well as enduring stability of PSCs which fabricated in atmospheric environment. We employ the L-aspartic acid (L-Asp) buffer layer which rich in amino acids, the cross-linking Sodium Glycinate (SG) additive with carboxylate and small amount of 2-Hydroxyacetophenone (2-HA) containing carbonyl groups to modify the bottom, inner and top parts of perovskite films, respectively. As a result, the passivated internal and surface defects of perovskite film could achieve an enlarged average grain size (500 nm) and display more defect-less, dense morphology. The strengthened interfacial charge transport ability can significantly improve the photovoltaic performance of devices. Consequently, the optimized PSC bring about the negligible hysteresis of photocurrent and a dramatic 20.71% PCE. Moreover, the temperature and moisture stability of optimized PSCs are both remarkably enhanced. The normalized PCE of un-encapsulated device which modified via 2-HA could still retain 80% of its original value after placed in the dark for 100 hours at 50% relative humidity and 85 °C, simultaneously. Overall, this simple and practical strategy supplies a hopeful channel to facilitate the commercialized PSCs.
研究领域:
材料科学
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能源技术
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化学工程
✓ 已验证
DOI
高影响因子
Molecular Catalysis
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2020
·
IF 3.687
Ping Wei,Peng Chao,Yao-Ying Wang,Dong-Li Li,Qing-Jian Zou,Min-Hua Zong,Wen-Yong Lou
( S )-1-Phenyl-1,2-ethanediol (PED) is a vital chiral block in specialty chemical industries. The biotransformation of 2-hydroxyacetophenone (2-HAP) to ( S )-PED was conducted successfully catalyzed with BL21(DE3)(pETDuet- gst -mut- accr - gdh ) which harboring a carbonyl reductase mutant (mut-AcCR). The catalytic activity of the biocatalyst was 15.9 times higher than the recombinant cells harboring original AcCR. 250 mM 2-HAP was reduced, under optimal conditions, and the yield and space-time yield were 95.2 % and 1.89 M/d in the buffer system. Then C 4 MIMI·PF 6 was chosen to be the second phase to improve the catalytic efficiency, and the substrate concentration was increased to 450 mM in the C 4 MIMI·PF 6 /buffer system. After a reaction duration of 3 h, the product yield was over 92 %, and the space-time yield increased to 2.88 M/d which was 1.52 folds higher than that in the buffer system. Also, the product e.e. was over 99 % consistently. Overall, the preparative scale reduction of 2-HAP (450 mM) in C 4 MIMI·PF 6 /buffer system was conducted with promising result. The developed effective C 4 MIMI·PF 6 /buffer system of asymmetric reduction catalyzed by BL21(DE3)(pETDuet- gst -mut- accr - gdh ) will promote the preparation of the enantiomeric pureity chiral alcohol at industrial scale.
研究领域:
生物化学
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工业微生物学
✓ 已验证
产品关联
DOI
高影响因子
FLUID PHASE EQUILIBRIA
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2025
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IF 2.7
Junwei Cui,Abdul Mosaur Waseel,Qing Duan,Yike Gao,Chenyang Zhang,Tao Yang,Shengshan Bi
Hydrogen (H 2 ) solubility in liquid organic hydrogen carriers (LOHCs) is crucial for their widespread applications. This work investigates the solubility of H₂ x in two promising LOHCs: Acetophenone (APO) and 1-Methylnaphthalene (1-MN). Measurements were conducted using an isochoric saturation method within a temperature range of 293 to 363 K and pressures up to 5.8 MPa. The liquid densities ρ of APO and 1-MN, essential for characterizing H₂ solubility, were measured using a vibrating tube densitometer (DMA5000 M) at approximately 0.1 MPa. The experimental ρ for APO and 1-MN were compared with literature data and good agreement can be found. The Krichevsky-Kasarnovsky(K-K) equation was employed to correlate H₂ solubility x in APO and 1-MN, with deviations of mostly within 6 % and 10 %, respectively. Following, the behavior of H₂ solubility x concerning pressure along isothermal lines was analyzed. Finally, the thermodynamic parameter of dissolution of the two binary systems were studied. The enthalpy of dissolution is positive for all the systems, while the entropy of dissolution is negative. Under the same temperature, the Gibbs free energy of dissolution for the H₂ + APO system is smaller than that of the H₂ + 1-MN system.
研究领域:
化学工程
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物理化学
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产品关联
DOI
高影响因子
JOURNAL OF BIOTECHNOLOGY
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2016
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IF 2.667
Zhi-Mei Cui,Jian-Dong Zhang,Xiao-Jun Fan,Gao-Wei Zheng,Hong-Hong Chang,Wen-Long Wei
Optically pure 1-phenyl-1,2-ethanediol is a very important chiral building block and intermediate in fine chemical and pharmaceutical industries. Reduction of 2-hydroxyacetophenone provides a straightforward approach to access these important compounds. In this study, two enantiocomplementary carbonyl reductases, BDHA (2,3-butanediol dehydrogenase from Bacillus subtilis ) and GoSCR (polyol dehydrogenase from Gluconobacter oxydans ) were discovered for the first time to convert 2-hydroxyacetophenone (2-HAP) to ( R )-1-phenyl-1,2-ethanediol (( R )-PED) and ( S )-1-phenyl-1,2-ethanediol (( S )-PED) with excellent stereochemical selectivity, respectively. The two enzymes were purified and characterized. In vitro bioreduction of 2-HAP catalyzed by BDHA and GoSCR coupled with glucose dehydrogenase (GDH) from Bacillus subtilis for cofactor regeneration were demonstrated, affording both ( R )-PED and ( S )-PED in >99% ee and 99% conversion. Recombinant Escherichia coli whole cells co-expressing both GDH and BDHA or GoSCR genes were used to asymmetric reduction of 2-HAP to ( R )-PED or ( S )-PED. Under the optimized conditions, the bioreduction of 400 mM (54 g/L) substrate was proceeded smoothly without the external addition of cofactor, and the product ( R )-PED and ( S )-PED were obtained with 99% yield, >99% ee and 18.0 g/L/h volumetric productivity. These results offer a practical biocatalytic method for the preparation of both ( R )-PED and ( S )-PED with high volumetric productivity.
研究领域:
生物化学
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制药工程
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工业微生物学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Ziqi Zhao,Shaokun Liang,Chengjun Kang,Zhaoqiang Zhang,Liqin Zhou,Zhenxia Zhao,Xingzhen Qin,Yushan Pang,Hongbing Ji,Kungang Chai
Adsorption is considered as a promising method to purify the mixed acetophenone (AP) and 1-phenylethanol (1-PE) that are generally difficult to separate. Many efforts have been made to improve the preferential uptake of AP over 1-PE in aqueous phase, but there exists a practical bottleneck associated with their limited aqueous solubility. Herein, we demonstrate unprecedented reversal of selectivity in the organic medium enabled by β-ketoenamine-linked covalent organic frameworks (COFs), which were fabricated successfully by polycondensation between 1,3,5-triformylphloroglucinol (Tp) and diamines. The dependence of selective adsorption ability toward 1-PE on pore size was firstly investigated experimentally, indicating that TpBZ-COF with moderate pore size outperformed other analogues. The adsorption behaviors of 1-PE and AP onto TpBZ-COF were examined systematically. The evaluation results revealed a strong affinity toward 1-PE versus AP as well as excellent stability in recycling experiments. Further, the dynamic breakthrough experiments confirmed the practical application potential and remarkable recyclability. To probe the mechanism and structure–activity relationship, an imine-linked COF possessing similar porous structure was used as a reference for comparison of separation performance both experimentally and theoretically. The occurrence of hydrogen bonding between the hydroxyl of 1-PE and β-ketoenamine-linkage as H-bond acceptor in suitable pore spaces endows TpBZ-COF a fantastic candidate for purifying 1-PE and AP from petrochemical by-products.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
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2019
·
IF 4.027
Wen-Jia Dan,Qiang Zhang,Fan Zhang,Wei-Wei Wang,Jin-Ming Gao
In this article, 23 compounds (6 and 7a–7v) were prepared and evaluated for their in vitro α-glucosidase inhibitory activity. The compounds 7d, 7f, 7i, 7n, 7o, 7r, 7s, 7u, and 7v displayed the α-glucosidase inhibition activity with IC50 values ranging from 1.68 to 7.88 µM. Among all tested compounds, 7u was found to be the most efficient, being 32-fold more active than the standard drug acarbose, which significantly attenuated postprandial blood glucose in mice. In addition, the compound 7u also induced the fluorescence quenching and conformational changes of enzyme, by forming α-glucosidase–7u complex in a mixed inhibition type. The thermodynamic constants recognised the interaction between 7u and α-glucosidase and was an enthalpy-driven spontaneous exothermic reaction. The synchronous fluorescence and CD spectra also indicate that the compound 7u changed the enzyme conformation. The findings identify the binding interactions between new ligands and α-glucosidase and reveal the compound 7u as a potent α-glucosidase inhibitor.
研究领域:
药理学
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有机化学
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代谢疾病研究
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2025
·
IF 5.5
Jinmin Wang,Chenkai Chu,Mingming Fang,Yongxin Tao,Yong Qin,Zheng Liang
The structure of covalent organic framework nanosheets (COF NSs) effectively mitigates fluorescence quenching caused by π–π stacking. Designing functionalized COF NSs as luminescent materials represents an innovative approach to expanding research on COF-based fluorescence sensing. Given that COF NSs expose a greater number of binding sites, they can be functionalized with appropriate luminescent elements to form a COF NS composite. The interaction between analytes and COF NS composites results in significant changes in luminescence, making these composites promising candidates for chemosensing applications. In this study, we introduce functionalized dual luminescent centers (silicon quantum dots (SiQDs) and Eu3+ complexes) into COF skeletons via a modification-facilitated exfoliation strategy. This process transforms the bulk COF (MPCOF) into a COF NS composite (1) with an enhanced luminescent performance. As a fluorescent sensor, 1 detects the biomarker 2-aminoacetophenone (2-AA) from Pseudomonas aeruginosa using ratiometric signals, facilitating visual sensing analysis. Leveraging its high sensitivity, an algorithmic method based on deep learning has been established to predict the fluorescence response of sensor 1 to specific concentrations of 2-AA. This facile determination of 2-AA enables effective monitoring of human or animal health and evaluation of water environments.
研究领域:
生物化学
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医学检测
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材料科学
·
人工智能
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2018
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IF 8.097
Chen Jiao,Yuanyuan Chen,Tianqi Liu,Xin Peng,Yaxin Zhao,Jianan Zhang,Yuqing Wu,Huiliang Wang
Shape memory hydrogels (SMHs) have a wide range of potential practical applications. However, the mechanically weak and soft nature of most SMHs strongly impedes their applications. Here, we report a novel kind of thermal-responsive SMH with high tensile strength and high elastic moduli. Organogels are first prepared by the copolymerization of a hydrophilic monomer N-vinylpyrrolidone (NVP) and a hydrophobic monomer acryloxy acetophenone (AAP) in N,N′-dimethylformamide (DMF) solutions, and then, poly(vinylpyrrolidone-co-acryloxy acetophenone) [poly(NVP-co-AAP)] hydrogels are obtained by solvent exchange with water. Because of the strong and reversible hydrophobic association and π–π stacking of acetophenone groups, the poly(NVP-co-AAP) hydrogels exhibit tensile strengths up to 8.41 ± 0.83 MPa and Young’s moduli up to 94.2 ± 1.3 MPa, which are more than 1 or 3 orders of magnitude higher than those of the organogels, respectively. The poly(NVP-co-AAP) hydrogels exhibit good shape memory behaviors, with a complete fixation ratio and a recovery ratio of 74–89%, as well as very fast shape-fixing and recovering rates (in seconds). These rigid and strong hydrogels are demonstrated to be an ideal shape memory material for surgical fixation devices to wrap around and support various shapes of limbs.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）