Molecular Catalysis
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2024
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IF 3.9
Lizhen Qin,Jingying Wang,Huihui Mao,Lvjie Ge,Chao Yao
Development of heterogeneous catalysts with both Brønsted and Lewis acid properties has proved to be promising and useful because they offer an efficient way to cascade reactions. In this study, we present the synthesis pathway and efficacy evaluation of new composites which combined by sulfonic acid functional group modified TiO 2 and MIL-101, analyzing their structure-performance correlation as heterogeneous catalysts in cascade reactions involving esterification, hydrogen transfer, and lactonization. These composites possess an open porous structure (MOF and porous TiO 2 ), as well as active sites including Lewis acid (unsaturated coordination metal), Lewis base (Ti-OH), and Brønsted acid (-SO 3 H). The role of these active sites and the synergies between them were investigated through the esterification of levulinic acid and the direct synthesis of γ-valerolactone from levulinic acid and furfural under cascade reactions. The composites exhibit a 100% ethyl levulinate (EL) yield at 120°C for 6 hours, with γ-valerolactone yields reaching up to 94.5% (160 °C, 9 h) and 89.5% (160 °C, 16 h) from levulinic acid and furfural, respectively. This synergistic effect of Lewis acid/base and Brønsted acid ensures efficient esterification. The presence of a sulfonic acid group promotes the lactonization reaction, while the Meerwein-Ponndorf-Verley reduction is facilitated by the dual Cr sites located adjacent to each other in the secondary building unit of MIL-101(Cr). Moreover, the double-porous structure of porous TiO 2 and MIL-101(Cr) effectively guarantees the efficient mass transfer of reactants and intermediates, leading to enhanced synergistic effects that promote more efficient reaction conversion.
研究领域:
化学工程
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催化科学
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产品关联
DOI
高影响因子
Bioresources and Bioprocessing
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2021
·Vol. 8
·期 1
·1-9
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IF 4.578
Zhang Xiaowang,Tan Zhuotao,Li Chaojian,Qi Siyu,Xu Mengjiao,Li Ming,Xiong Wenlong,Zhuang Wei,Liu Dong,Zhu Chenjie,Ying Hanjie
Background Lactones are important compounds in the field of medicine, material and chemical industry. One of the promising accesses to these flexible scaffolds is NAD(P) + -dependent alcohol dehydrogenases-catalyzed oxidative lactonization of diols, which relies on the construction of an efficient NAD(P) + regeneration system. Results In this study, a novel system combining horse liver alcohol dehydrogenase (HLADH) with the synthetic bridged flavin cofactor was established for biosynthesis of lactones. The reaction conditions of this system were optimized and a variety of lactones including chiral lactones were efficiently obtained from various diols. Compared to the previously reported NAD(P) + -regeneration systems, this system showed better regeneration efficiency and product yield. A two-phase system was further applied to solve the problem of product inhibition, and 80% yield was obtained at the condition of 300 mM substrate. Conclusions This study provides an efficient method to synthesis of lactones from diols under mild conditions. We believe this system will be a promising alternative to promote the synthesis of other valuable compounds. Graphic abstract
研究领域:
生物催化
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化学生物学
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有机化学
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药物化学
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产品关联
DOI
PubMed
高影响因子
Journal of Future Foods
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2025
·Vol. 6
·期 1
·66-72
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IF 7.2
Hao Zhang,Bin Wu,Yanping Xian,Ming Liang,Yunjian Ma,Yonghua Wang
Musk macrolides are a kind of rare flavors structurally featuring 14−16 membered rings in the flavour and fragrance industry. While various chemical synthesis routes for musk macrolides exist, there is a growing interest in biocatalytic approaches. In this study, a new biocatalytic approach is proposed for the synthesis of musk macrolides from fatty acids using unspecific peroxygenases (UPOs) in combination with lipase. Specifically, the UPO from Marasmius rotula ( Mro UPO) was utilized as an oxidation catalyst together with the choline oxidase from Arthrobacter nicotinate ( An ChOx) for the in situ generation of H 2 O 2 . The enzymatic cascade process involved the hydroxylation of fatty acids using Mro UPO as a catalyst to prepare terminal hydroxylated fatty acids. Under the optimized conditions, 14-hydroxy tetradecanoic acid, 15-hydroxy pentadecanoic acid and 16-hydroxy hexadecanoic acid were obtained at concentrations of 11.1, 18.2 and 17.1 mg/L in a 50-mL reaction system, respectively. These hydroxylated fatty acids were then separated and esterified by lipase Novozymes 435 to produce the desired macrolides. Various ω -hydroxy fatty acids were successfully converted into macrolides, with the concentrations of cyclotetradecanolide, cyclopentadecanolide and cyclohexadecanolide reaching 11, 29 and 23 mg/L, respectively, in a 10-mL reaction system. This new biocatalytic approach represents a promising method for synthesizing valuable natural flavour compounds.
研究领域:
生物催化
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酶工程
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天然产物化学
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风味化学
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分子生物学
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绿色合成
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DOI
高影响因子
JOURNAL OF CATALYSIS
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2023
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IF 7.3
Duoyue Tang,Zewen Shen,Sebastian Lechler,Guilong Lu,Ling Yao,Yezi Hu,Xiubing Huang,Martin Muhler,Guixia Zhao,Baoxiang Peng
Lactones are applied in pharmaceutical or agriculture/forestry industry as anesthetics/sedatives, pesticide intermediates or as plant growth regulators. Selective conversion of diols into value-added lactones under mild reaction conditions is still challenging. Here, we report on an environmentally benign catalytic approach using oxygen vacancies-enriched titanium-based oxides and water as solvent at room temperature for the lactonization of various aromatic and aliphatic diols. Lactonization was found to proceed in two consecutive steps: 1) the dehydrogenation of diols to hydroxyaldehyde intermediates catalyzed by the Pt cocatalyst; 2) the subsequent oxidative lactonization of the intermediates to the lactone products over defective titanium-based oxides. Diffuse reflectance infrared Fourier transform spectroscopy analysis using pyridine as probe molecule combined with electron paramagnetic resonance results suggest that oxygen vacancies as strong Lewis acid sites are pivotal for the superior catalytic activities at room temperature, which are attributed to the enhanced reaction rate of step 2 due to stronger adsorption of the hydroxyaldehyde intermediates on the Lewis acid sites.
研究领域:
催化
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有机化学
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环境科学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2019
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IF 6.361
Zhengzhou Su,Chunmei Li,Jiaojun Tan,Ying Xue,Guoxian Zhang,Yumin Yang,Qiuyu Zhang
Oil-in-oil emulsions are ideal systems for water-sensitive reactions such as polymerizations and catalytic reactions , which has received extensive attention in recent years. The application of oil-in-oil emulsions has been developed slowly due to the limited types of surfactants and complicated synthesis process. Herein, we proposed a simple method to prepare poly(amide-thioether)-based surfactant for oil-in-oil emulsions via taking advantage of single-pot multicomponent and click characters of thiolactone chemistry. Using a combination of alkyl amine and acrylamide thiolactone, the aminolysis of thiolctone occurred first, generating thiol group in-situ, and then the generated thiol group would sequentially react with the double bonds of acrylamide to form polythioether in the presence of amine. The hydrophobicity of the surfactant could be effectively adjusted by the chain length of the alkyl amine and thus this polymer could serve as a promising surfactant for oil-in-oil emulsion. Notably, the emulsion types could be switched by changing the chain length of the alkyl amine. In addition, the effects of surfactant loading, volume ratio of oil phases, oil types on the size and stability of oil-in-oil emulsions were further investigated. It was demonstrated that the oil-in-oil emulsion stabilized by poly(amide-thioether)s kept stable after more than five months. Besides, we preliminarily explored the application of the oil-in-oil emulsion to prepare closed cell foam and porous particles via photo-initiated thiol-ene polymerization. It is believed that this super-stable oil-in-oil emulsion could offer more possibilities for highly potential water-sensitive systems.
研究领域:
高分子化学
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胶体与界面科学
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材料科学
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化学工程
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软物质物理
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DOI
高影响因子
Molecular Catalysis
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2023
·
IF 4.6
Pei-Sen Gao,Chang-Wang Pan,Cheng Liu,Wen-Tong Chen
Asymmetric electrocatalysis is poised to provide a unique avenue for access to enantioenriched molecules that are difficult to obtain through more conventional approaches, but the development of efficient electrocatalysts capable of highly enantioselective transformations remains elusive. Towards this enviable end, bifunctional electrocatalyst capable of both redox mediation and delivery of high stereocontrol is needed. Here we disclose a novel TEMPO-BOX-ligated copper electrocatalyst that enables oxidative kinetic resolution of racemic 1,4-diols, affording diverse chiral 1,4-diols and γ-lactones with good or excellent chemo-, regio, and enantioselectivity. We also show that this cooperative Cu/TEMPO-BOX catalytic strategy is applicable to the electro-oxidative kinetic resolution of 1,2- and 1,3-amino alcohols. This work demonstrates the potential of bifunctional electrocatalysis for asymmetric synthetic methods and we anticipate that it will spur the development of new hybrid electrocatalysts to realize novel asymmetric electrocatalytic methods.
研究领域:
有机化学
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电化学
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催化
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合成化学
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DOI
高影响因子
ACS Applied Materials & Interfaces
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2022
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IF 10.383
Guoxian Zhang,Chunmei Li,JiaoJun Tan,Mingqi Wang,Zongxu Liu,Yafeng Ren,Ying Xue,Qiuyu Zhang
Polyurethane elastomers with mechanical robustness, tear resistance, and healing efficiency hold great potential in wearable sensors and soft robots. However, achieving excellent mechanical properties and healable capability simultaneously remains highly desirable but exclusive. Herein, we propose a straightforward procedure for double modification of poly(urethane-urea) (PUU) via thiolactone chemistry, and two different dynamic cross-linking bonds (disulfide linkages and Zn2+/imidazole coordination) are successively incorporated into the side chain of PUU, producing double cross-linking elastomers (PUU–I/Zn–S). The synergy between disulfide linkages and Zn2+/imidazole coordination forms a robust and dynamic network, endowing PUU–I/Zn–S with excellent mechanical and healing properties. The tensile stress, elongation at break, and toughness of the resultant elastomer can reach 44.06 MPa, 1000%, and 181.93 MJ m–3, respectively. Meanwhile, PUU–I/Zn–S exhibits outstanding tearing resistance with a tearing energy of 42.1 kJ m–2. The PUU–I/Zn–S can restore its mechanical robustness after self-healing at room temperature (25 ± 2 °C) or 60 °C and even maintain 91% of its original tensile strength after reprocessing two times. Additionally, PUU–I/Zn–S-based strain sensors are fabricated by introducing conductive nanofillers and demonstrate remarkable sensing capability to diverse human body motions. This work demonstrates a simple and feasible method for the postfunctionalization and enhancement of polyurethane and provides some insights into reconciling the traditional contradictory properties of mechanical robustness and healing efficiency.
研究领域:
材料科学
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高分子化学
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机械工程
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可穿戴技术
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DOI
高影响因子
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