Journal of CO2 Utilization
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2018
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IF 5.503
Xianting Cao,Haizhen A. Zhong,Pengfei Zhang,Hui Zheng
A simple chemical fixation of CO 2 at atmospheric pressure to make valuable benzimidazolones derivates via the o -phenylene-diamines carbonylation reaction catalyzed by DBU/S was developed. Different reaction conditions were examined and optimized. A series of benzimidazolones derivatives were synthesized using NMP as solvent at 413K with excellent yields (80–94%). Various substrates were employed and the results suggested the wide application of our method. The quantum mechanics calculations demonstrated that the complexation of DBU with sulfur significantly enhanced the reaction. This protocol rovides a novel approach of fixing CO 2 at atmospheric pressure into a series of 2-benzimidazolones derivates.
研究领域:
有机化学
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环境科学
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DOI
高影响因子
MACROMOLECULES
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2018
·
IF 5.914
Zhitao Hu,Yi Chen,Huahua Huang,Lixin Liu,Yongming Chen
This article demonstrates the synthesis of a new kind of cationic poly(δ-valerolactone) with primary amino groups at α-positions (poly(α-NH2-VL)) via ring-opening polymerization (ROP) of α-NHBoc-valerolactone (α-NHB-VL) followed by a simple deprotection reaction. The ROP of α-NHB-VL using benzyl alcohol as an initiator and DBU/TU (1,8-diazabicyclo[5.4.0]undec-7-ene/thiourea) as a catalytic system in THF at room temperature afforded poly(α-NHB-VL) with narrow molecular weight distribution. The 1H NMR and MALDI-TOF MS analysis of poly(α-NHB-VL) indicated that each polymeric chain was capped by the initiator. Kinetic experiments confirmed the living nature of the DBU/TU-catalyzed ROP of α-NHB-VL in THF. The copolymerization result indicated that the polymerization activity of α-NHB-VL is comparable to that of ε-caprolactone (CL) and VL. In addition, block copolymers containing poly(α-NHB-VL) were successfully synthesized regardless of whether hydrophilic PEG or hydrophobic PCL was used as the macroinitiator. Moreover, water-soluble poly(α-NH2-VL) was obtained by treatment with trifluoroacetic acid (TFA). It was found that poly(α-NH2-VL) degraded more slowly at pH 5.5 than at pH 7.4 through a hydrolysis kinetics study.
研究领域:
高分子化学
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材料科学
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生物医学工程
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DOI
高影响因子
Journal of CO2 Utilization
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2021
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IF 7.132
Jianfei Sun,Zhuojian Li,Jianzhong Yin
Self-synthesis of green and high-efficiency DBU-based ionic liquid catalyst immobilized on SBA-15, conversion of CO 2 into PC through the use of packed bed reactors. Tableting and changing the type of filler were adopted to tune the padding pattern of the catalyst in the reactor and improve the flow channel status. The effect of reaction temperature (45 ℃-90 ℃), operating pressure (1 MPa–4 MPa), CO 2 flow rate (5 mL/min-100 mL/min), reaction time (2 h–8 h) on the yield of continuous flow synthesis of PC was investigated, and the catalyst activity also was evaluated by continuous use for 30 h. The intimate and direct contact of binary fluids leads to enhanced mass transfer and promoted reactions. Screen the optimal process conditions were 90 °C, 2 MPa, PO flow rate 0.1 mL/min, CO 2 flow rate 5 mL/min, after continuous reaction for 2 h, the yield of PC could be achieved the highest, 57.10 %. Compared with the conventional batch reactor, the substrate was consumed immediately in the continuous reaction, and the product was generated in situ, and the reaction was safe and efficient, which provides guidance for industrial scale-up.
研究领域:
化学工程
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环境科学
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催化反应
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DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2022
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IF 6.633
Tingting Chen,Yingjie Xu,Bin Chen,Huiquan Xiao
In this work, the efficient preparation of zeolitic imidazolate framework-8 (ZIF-8) from Zn 2+ and 2-methylimidazole (2-MI) promoted by 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) was presented. The mechanism obtained from NMR, MS, DFT calculations, and conductivity shows that [DBUH][2-MI] ionic liquid formed in-situ from proton transfer between DBU and 2-MI can ionize 2-MI to [2-MI] - and form electrostatic interaction between Zn 2+ and [2-MI] - , resulting in the efficient self-assembly of Zn 2+ and 2-MI to form ZIF-8. Moreover, the effect of the amount of DBU on ZIF-8 indicates that too much DBU will cause excessive deprotonation of 2-MI, leading to agglomerate of ZIF-8. Accordingly, the optimal ratio to form ZIF-8 is n(DBU): n(2-MI): n(Zn 2+ ) = 2: 25: 1.25, which is also employed to prepare cerium-containing ZIF-8. Moreover, ZnO and Ce/ZnO nanomaterials are prepared by using ZIF-8 and cerium-containing ZIF-8 as precursors respectively, and their structure and morphology are characterized by XRD, FT-IR, SEM, and TEM. Interestingly, Ce content in Ce/ZnO obtained by EDS spectrum is basically consistent with the actual doping amount, indicating that DBU can effectively control the doping of Ce in ZIF-8. Finally, the photocatalytic degradation ability of ZnO and Ce/ZnO for Rhodamine B under visible light and sunlight is investigated in detail.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2023
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IF 6
Wentao Zheng,Guangwen Yu,Guibing Xia,Wanghao Shen,Weizhong Shi,Tengteng Zhou,Xiankun Wu
Developing absorbents with highly efficient nitric oxide (NO) absorption and desorption is very important for flue gas denitrification process. Toward this end, a class of DBU-based deep eutectic solvents (DESs) containing alkanones or azoles as functional HBDs for the capture of NO were synthesized in this work, with viscosities of only 7.71–45.57 mPa·s at 303.2 K. Solubilities of NO in these DESs were determined at temperatures from 303.2 to 333.2 K and pressures from zero to 1 bar. It was found that the absorbing abilities of the DESs increased with the increasing HBDs’ alkalinity. Impressively, these DBU-based DESs had remarkable larger absorption capacities than those reported DESs in the literature. According to the solubility curves of NO, chemical absorption was thought to occur accompanying with the physical one in the systems. Therefore, the reaction equilibrium thermodynamic model (RETM) was applied to model the experimental NO solubilities. The corresponding thermodynamic parameters for each system, such as the reaction equilibrium constant, Henry’s law constant, and the enthalpy change were also obtained to assess the NO absorption process in these DESs.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
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2023
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IF 5.9
Gu Guo,Yuanlong Guo,Hailiang Sheng,Pengcheng Liu,Lei Dai,Michael North,Lei Deng,Xiaofeng Luo,Haibo Xie
A series of cellulose grafted alternating cyclic anhydride (CA) and epoxide (EPO) copolyesters (cell- g -P(CA-alt-EPO)) have been prepared in the novel DBU/DMSO/CO 2 cellulose solvent system. The DBU acted both as a reagent for cellulose dissolution and as a catalyst for ring-opening copolymerization (ROCOP) of cellulose with EPO and CA. The structural features and thermal performances of cell- g -P(CA-alt-EPO) were characterized via MALDI-TOF, FT-IR NMR, TGA, DSC and XPS. Perfectly alternating sequence distributions and controlled molecular weights of a series of cell- g -P(CA-alt-EPO) were easily achieved by a variation of the CA or EPO. The cell- g -P(CA-alt-EPO) also had satisfactory UV-absorbing properties and cellulose grafted phthalic anhydride and glycidyltrimethylammonium chloride exhibited outstanding antibacterial behavior. Antibacterial activity against Escherichia coli and Staphylococcus aureus were 96.7% and 99.4% respectively. Thus, cell- g -P(CA-alt-EPO) with good solubility, melt processability, UV absorption and antibacterial properties have potential applications in UV-shielding and antibacterial agent fields.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2025
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IF 7.3
Jingyu Chen,Dingyi Duan,Sen Xue,Yongzheng Zhang,Kai Wu,Qiang Fu
Owing to the limited solubility of cellulose in conventional solvents, the development of efficient solvent systems to dissolve cellulose is necessary for its subsequent processing into value-added cellulose-based materials. In recent years, a green, low-cost, and sustainable CO2-based reversible solvent system (CO2/DMSO/DBU) has been developed. In this system, dimethyl sulfoxide (DMSO) facilitates the swelling of cellulose, and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) provides a strong alkaline environment, enabling the derivatization of cellulose with CO2 to form cellulose carbonate, which is soluble in the solvent. Nevertheless, these systems have drawbacks, including high temperature (>50 °C) and inadequate mechanical properties of the regenerated cellulose films. In this study, ball milling was used to lower the dissolution temperature of cellulose and further improve the mechanical properties of regenerated cellulose films. To do this, dry ice as a source of CO2 and DMSO/DBU as mixed solvents, together with cellulose, were ball-milled at room temperature. A series of regenerated cellulose films were prepared at different dry ice contents and ball milling times. The results demonstrate that the cellulose can be readily dissolved within 0.5 h at room temperature, resulting in a stable cellulose solution (4.48 wt%), thanks to the mechanochemistry provided by ball milling. The prepared regenerated cellulose films exhibit satisfactory mechanical properties with a tensile strength of up to 77.3 MPa and a tensile strain of 8.6%, which are among the highest values reported for regenerated cellulose films. This work illustrates a simple, mild, and efficient method for green cellulose processing.
研究领域:
高分子科学
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材料工程
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绿色化学
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机械化学
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纤维素加工
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2022
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IF 6.633
Wentao Zheng,Guibing Xia,Guangwen Yu,Qian Cai,Xiankun Wu,Weizhong Shi
A series of low viscous deep eutectic solvents composed of 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) and N-heterocyclic compounds were designed and synthesized as NO trapping agents. These DESs exhibited low viscosity of 10.02 mPa·s and excellent NO absorption capacity up to ∼ 5.10 mol·kg −1 at 293.2 K and atmospheric pressure. The N-heterocyclic compounds were found to play a dominant role in the absorption, and the absorption behavior could thus be adjusted by the molar ratio of DBU to N-heterocyclic compounds. With the assumption of complex formation between NO and DESs, the reaction equilibrium thermodynamic model (RETM) was developed to correlate the experimental solubilities of NO. The thermodynamic parameters, such as the equilibrium constant K , the Henry’s constant H and the enthalpy change Δ H , were thus calculated to evaluate the absorption process. In addition, through a combination of the experimental absorption capacities, the RETM modeling results and the spectroscopic investigations, it was proposed that the absorption of NO in the DBU-based N-heterocyclic DESs was governed by the chemical interaction between NO and the N atom on the N-heterocyclic compounds with the reaction stoichiometry of 1:1.
研究领域:
化学工程
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环境科学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2023
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IF 8.2
Xiangli Gao,Huan Liu,Jianbo Shuai,Junmeng Zhao,Guowen Zhou,Quanbo Huang,Hao Ling,Wenjiao Ge,Xiaohui Wang
Cellulose acetate (CA) is one of the most important cellulose plastics that has demonstrated extensive applications in many areas. In search of a more sustainable and efficient way to prepare CA, we synthesized a novel ionic liquid , [DBUC 8 ]Cl, based on the commonly used catalyst DBU (1,8-diazabicyclo[5.4.0]undecyquin-7-ene) in a simple manner. [DBUC 8 ]Cl can dissolve cellulose more efficiently than the same type of imidazolyl ionic liquid, owing to the stronger alkalinity of DBU. It is noteworthy that highly substituted CA (DS = 2.82) was successfully synthesized via transesterification with alkenyl ester under mild conditions (80 °C, 40 min) without the addition of a catalyst in this solvent, which is superior to most of the reported work. Furthermore, we confirmed that the synthesized CA had good thermoplasticity, and a transparent cellulose acetate film (CAF) was obtained by hot pressing with a small amount of glycerol. Therefore, we propose a new DBU-derived ionic liquid, which may serve as a versatile platform system for producing cellulose-derived bioplastics more sustainably and efficiently.
研究领域:
化学工程
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材料科学
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产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
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2022
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IF 5.089
Mantong Xue,Jianfei Sun,Xintong Li,Jianlei Qi,Qinqin Xu,Jianzhong Yin
Emissions of carbon dioxide can lead to the greenhouse effect, causing global warming and so on. conversion of carbon dioxide into high-value chemicals through catalysis, which is an effective method to successfully curb carbon emissions and prevent the greenhouse effect. Among them, CO 2 chemical synthesis of cyclic carbonate is one of the important way. In this paper, a new type of supported ionic liquid catalyst (GO-[DBU][Br]) was synthesized by one-pot method. Subsequently, the GO-[DBU][Br] was applied to the cycloaddition reaction of CO 2 in batch reaction and fixed bed continuous reaction, respectively. The stability of the catalyst was also explored, the GO-[DBU][Br] was easily separated and reused at least 5 times without significant loss of catalytic activity. The excellent catalytic performance comes from the synergistic effect of ionic liquid cations, halogenated anions, and a large number of oxygen-containing functional groups on the GO surface, a possible reaction mechanism was thus proposed. The study provides a safe, efficient, and industrial-scale continuous reaction system for CO 2 utilization.
研究领域:
化学工程
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF THE CHINESE CHEMICAL SOCIETY
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2020
·Vol. 67
·期 9
·1715-1720
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IF 1.554
Shu-Zhen Yang,Zhi-Qiang Dong,Cheng-Cheng Yin,Hui-Juan Yue,Wei-Wei Gao,Feng-Ke Yang
In this paper, a green process for the synthesis and separation of caffeine was reported. Theophylline sodium is used as the raw material, diazabicyclo[5.4.0]undec-7-ene as the catalyst, and Turkey red oil as the solvent, particularly, dimethyl carbonate was adopted in place of high toxic dimethyl sulfate to form a mixture of caffeine and by-product sodium bicarbonate. After converting sodium bicarbonate to sodium carbonate, the solubility difference between caffeine and sodium carbonate at 40°C was for the first time utilized to achieve the purpose of separating caffeine with an excellent yield of 98.4% and a purity of greater than 99.0%. Furthermore, both the reaction mother liquor and separation mother liquor can be recycled and reused during the reaction and separation processes, respectively, with little caffeine loss. No industrial waste was discharged in the process of the improved synthesis and separation, which is therefore environmental friendly.
研究领域:
有机化学
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药物化学
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绿色合成
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分离科学
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环境科学
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DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2019
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IF 4.561
Hui Fu,Xinyu Wang,Haina Sang,Yunpeng Hou,Xihai Chen,Xiang Feng
New solvents have been developed to dissolve microcrystalline cellulose by easily prepared DBU-based deep eutectic solvents (DESs), which have excellent solvent power for biopolymers . Cellulose/[DBU][MTU] as a typical example for detailed analysis, which was characterized (by means of FT-IR and NMR) and studied as potential cellulose dissolution media. Furthermore, selecting cellobiose as a model for density functional theory (DFT) calculation. The hydrogen bonds were explored to evaluate the strength of interaction between DESs and cellulose, which is by means of atoms in molecules (AIM), natural bond orbital (NBO) and reduced density gradient (RDG). Spectroscopic and theoretical analyses are conductive to in-depth understanding of the dissolution mechanism: both of hydrogen bond acceptor and donor in DESs interact with cellulose, contributed to the dissolution behavior. Intermolecular interactions in the complexes have been identified as non-covalent interactions, especially hydrogen bonds , which were considered to be the driving force of dissolution.
研究领域:
材料科学
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生物化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）