ACS Sustainable Chemistry & Engineering
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2020
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IF 7.632
Di Li,Yanyan Gong,Minchen Du,Chao Bu,Cheng Chen,Somboon Chaemcheun,Jia Hu,Yongxing Zhang,Ye Yuan,Francis Verpoort
α-Hydroxy ketones are a series of biologically active fragments in nature as well as important synthons for organic chemistry. Herein, an AgOAc/1-ethyl-3-methylimidazolium acetate ionic liquid system was developed for the CO2-promoted hydration of propargylic alcohols and H2O to produce α-hydroxy ketones. Diverse desired products could be obtained in satisfactory yields under 1 bar of CO2 pressure with the catalysis of only a trace amount of silver (0.005–0.25 mol %), which is the lowest level ever reported for the metal-catalyzed systems. In particular, this system had robust recyclability, and it could be reused effectively at least 5 times. Furthermore, an unprecedented turnover number (TON) of 9200 was achieved, which is considered to be the highest TON ever reached for this hydration.
研究领域:
有机化学
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催化
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绿色化学
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
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2019
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IF 4.914
Yuzhuo Chen,Xiangqian Kong,Shanjun Mao,Zhe Wang,Yutong Gong,Yong Wang
The selective hydrogenation of phenol to cyclohexanone is an important process in the chemical industry. However, achieving high selectivity at high conversion rates is highly challenging, particularly under continuous reaction conditions. Here, we found that the presence of Na alkaline additives (NaX, X = CO 3 2– , HCO 3 – , or OH – ) on Pd/Al 2 O 3 not only promoted the phenol conversion from 8.3% to >99% but also increased the cyclohexanone selectivity from 89% to >97% during the continuous hydrogenation of phenol on a fixed bed reactor. After 1200 h of continuous reaction, no activity or selectivity attenuation was observed and the turnover number was approximately 2.9 × 10 5 . Density functional theory calculations, spectroscopic, and dynamics studies demonstrated that the addition of NaX greatly promoted phenol adsorption and hydrogen activation, thereby improving catalytic activity. Simultaneously, the formation of a “-C=O-Na-” intermediate inhibited the excessive hydrogenation and intermolecular coupling of cyclohexanone, leading to high selectivity.
研究领域:
催化化学
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有机化学
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工业化学
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表面化学
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计算化学
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
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2021
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IF 7.92
Ye Yuan,Jia Hu,Yu Wang,Leilei Huang,Jiayun Zheng,Yufeng Zhao,Yiyun Chen,Cheng Chen,Francis Verpoort
α-Hydroxy ketones are important building blocks in biological, pharmaceutical and synthetic chemistry. In this work, diverse α-hydroxy ketones were efficiently constructed through the CO 2 -promoted hydration process of propargyl alcohols, which was catalyzed by a system consisted of economical CuSO 4 ·5H 2 O and a green 1-butyl-3-methylimidazolium acetate ionic liquid. Particularly, this catalytic system exhibited excellent activity under atmospheric CO 2 or even mimetic flue gas (20 vol% of CO 2 ). Moreover, this system employed the lowest metal loading ever reported (0.004–0.25 mol%) meanwhile reached the highest turnover number (11700) for the target hydration reaction. Additionally, this is the first reported Cu catalytic system with reliable recyclability, which could be easily reused at least 6 times with yields higher than 85%.
研究领域:
催化
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绿色化学
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有机合成
✓ 已验证
DOI
高影响因子
Nature Energy
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2022
·Vol. 7
·期 11
·1042-1051
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IF 67.439
Zhang Lili,Liu Le,Pan Ziye,Zhang Rui,Gao Zhuoyang,Wang Guangming,Huang Keke,Mu Xiaoyue,Bai Fuquan,Wang Yan,Zhang Wei,Cui Zhonghua,Li Lu
Direct non-oxidative dehydrogenation of alkanes produces useful carbon feedstocks and hydrogen fuel. However, breaking the C–H bonds in alkanes typically requires high temperature, stoichiometric oxidants or high-energy ultraviolet light; processes that operate under milder conditions are attractive but tend to have poor efficiency. Here we report Pt/black TiO 2 photocatalysts in which Pt species are close to each other but not directly bonded, exhibiting high performance for alkane dehydrogenation in visible to near-infrared light at room temperature. For cyclohexane dehydrogenation, the turnover number for H 2 production exceeded 100,000 without any deactivation over 80 reaction cycles, far beyond thermal reactions. For methane, 8.2% conversion was achieved with 65% selectivity to propane, rather than the more common ethane. We propose that methane undergoes intramolecular dehydrogenation to produce a methylene intermediate. For C2+ alkanes, fast dehydrogenation (up to 1,440 µmol g −1 h −1 ) to the corresponding olefins was realized. Distinct from isolated Pt + monomers, the collections of Pt + monomers give better photocatalytic activity and selectivity.
研究领域:
化学
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催化
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材料科学
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能源
✓ 已验证
DOI
高影响因子
JACS Au
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2024
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IF 8.5
Yaoyun Wu,Yaozhong Cui,Wei Song,Wanqing Wei,Zhizhen He,Jinyang Tao,Dejing Yin,Xiulai Chen,Cong Gao,Jia Liu,Liming Liu,Jing Wu
l-Amino acid oxidase (LAAO) is an important biocatalyst used for synthesizing α-keto acids. LAAO from Rhodococcus opacus (RoLAAO) has a broad substrate spectrum; however, its low total turnover number limits its industrial use. To overcome this, we aimed to employ crystal structure-guided density functional theory calculations and molecular dynamic simulations to investigate the catalytic mechanism. Two key steps were identified: S → [TS1] in step 1 and Int1 → [TS2] in step 2. We reprogrammed the transition states [TS1] and [TS2] to reduce the identified energy barrier and obtain a RoLAAO variant capable of catalyzing 19 kinds of l-amino acids to the corresponding high-value α-keto acids with a high total turnover number, yield (≥95.1 g/L), conversion rate (≥95%), and space-time yields ≥142.7 g/L/d in 12–24 h, in a 5 L reactor. Our results indicated the promising potential of the developed RoLAAO variant for use in the industrial production of α-keto acids while providing a potential catalytic-mechanism-guided protein design strategy to achieve the desired physical and catalytic properties of enzymes.
研究领域:
生物催化
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酶工程
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计算化学
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蛋白质工程
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2022
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IF 10.383
Weiwei Li,Chunhua Zhang,Ziman Zheng,Xiaoyu Zhang,Lin Zhang,Alexander Kuhn
Electrochemical regeneration of the reduced form of the nicotinamide adenine dinucleotide (NADH) cofactor catalyzed by immobilized [Rh(Cp*)(bpy)Cl]+ is a promising approach for the enzymatic synthesis of many valuable chemicals with NAD-dependent dehydrogenases. However, rational control of the efficiency is often limited by the irregular structure of the electrode/electrolyte interface and the accessibility of the molecular catalyst. Here, we propose an electrochemical system for NADH cofactor regeneration, based on highly ordered three- dimensional (3D) metal–organic framework (NU-1000) films. [Rh(Cp*)(bpy)Cl]+ is incorporated at the zirconium nodes of NU-1000 via solvent-assisted ligand incorporation (SALI), leading to a diffusion-controlled behavior, associated with an electron hopping mechanism. Varying the ratio of redox-active [Rh(Cp*)(bpy)Cl]+ and inactive postgrafting agents enables the elaboration of functional electrodes with tunable electrocatalytic activity for NADH regeneration. The exceptionally high faradic efficiency of 97%, associated with a very high turnover frequency (TOF) of ∼1400 h–1 for NADH regeneration, and the total turnover number (TTN) of over 20000 for the enzymatic conversion from pyruvate to l-lactate, when coupled with l-lactate dehydrogenases (LDH) as a model reaction, open up promising perspectives for employing these electrodes in various alternative bioelectrosynthesis approaches.
研究领域:
电化学
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催化
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生物电化学
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材料科学
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DOI
PubMed
高影响因子
Journal of the American Chemical Society
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2024
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IF 14.4
Fan Ma,Zhi-Mei Luo,Jia-Wei Wang,Gangfeng Ouyang
The development of efficient, selective, and durable CO2 photoreduction systems presents a long-standing challenge in full aqueous solutions owing to the presence of scarce CO2 and the fierce competition against H2 evolution, which is even more challenging when noble metals are not utilized. Herein, we present the facile decorations of four phosphonic acid groups on a donor–acceptor-type organic dye to obtain a water-soluble photosensitizer (4P-DPAIPN), which succeeds the excellent photophysical and photoredox properties of its prototype, exhibiting long-lived delayed fluorescence (>10 μs) in aqueous solutions. Combining 4P-DPAIPN with a cationic cobalt porphyrin catalyst has accomplished record-high apparent quantum yields of 9.4–17.4% at 450 nm for CO2-to-CO photoconversion among the precedented systems (maximum 13%) in fully aqueous solutions. Remarkable selectivity of 82–93% and turnover number of 2700 for CO production can also be achieved with this noble-metal-free system, outperforming a benchmarking ruthenium photosensitizer and a commercial organic dye under parallel conditions. Such high performances of 4P-DPAIPN can be well maintained under real sunlight. More impressively, no significant decomposition of 4P-DPAIPN was detected during the long-term photocatalysis. Eventually, the photoinduced electron transfer pathways were proposed.
研究领域:
化学
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材料科学
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环境科学
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光化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMISTRY & BIODIVERSITY
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2022
·Vol. 19
·期 5
·e202200177
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IF 2.745
Susu Lin,Bingbing Ma,Qilin Gao,Jian Yang,Gang Lai,Runhao Lin,Bingxian Yang,Bing-Nan Han,Lian-Hua Xu
Cytochrome P450 enzymes (CYPs or P450s) are ubiquitous heme-dependent enzymes that catalyze the monooxygenation of non-activated C−H bonds to modify the structure of the substrate. In this study, we heterologously expressed CYP107X1 from Streptomyces avermitilis and conducted in vitro substrate screening using the alternative redox partners putidaredoxin and putidaredoxin reductase. CYP107X1 catalyzed the 16α-hydroxylation of progesterone with regio- and stereoselectivity. The spectroscopic analyses showed that CYP107X1 bound progesterone with a relatively high K d value of 65.3±38.9 μM. The K m and k cat values for progesterone were estimated to be 47.7±12.0 μM and 0.30 min −1 , respectively. Furthermore, a crystal structure was obtained of CYP107X1 bound with glycerol from the buffer solution. Interestingly, a conserved threonine was replaced with asparagine in CYP107X1, indicating that it may adopt an unnatural proton transfer process and play a crucial role in its catalytic activity.
研究领域:
生物化学
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酶学
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结构生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
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2020
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IF 2.726
Ding Guo,Cheng Li,Juan Zhang,Genyan Liu,Xiaogang Luo,Fengshou Wu
The chemical fixation of carbon dioxide to afford value added chemicals under solvent free and ambient conditions has gained considerable attentions. In this work, we successfully synthesized the porphyrin-based porous organic framework (PPOPs) through Schiff base reaction using 5,10,15,20-tetra(4-aminbiphenyl) porphyrin (TAPP) and 4,4′-biphenyldicarbaldehyde (BDA) as starting materials, which was then coordinated with cobalt to yield related metal complex (Co-PPOPs). The chemical structure and morphology of Co-PPOPs were characterized by absorption spectrum , FT-IR, X-ray photoelectron spectra (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD) and nitrogen physisorption . Co-PPOPs showed excellent catalytic activity towards the conversion of carbon dioxide to cyclic carbonates under ambient conditions. Furthermore, Co-PPOPs was recovered easily and could be used repeatedly (more than five times) without losing any catalytic activity. Thus, the as-prepared Co-PPOPs was a promising heterogeneous catalyst for carbon dioxide conversion, providing high turnover number than the previously reported catalysts.
研究领域:
材料科学
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催化
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绿色化学
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无机化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）