CHEMICAL ENGINEERING SCIENCE
·
2023
·
IF 4.7
Yakun Liu,Shennan Yang,Chengxiang Shi,Lun Pan,Xiangwen Zhang,Ji-Jun Zou
Simmons-Smith cyclopropanation commonly promoted by CF 3 COOH is one important method for transforming olefin into high-energy–density cyclopropyl fuel, but it brings problems such as high cost and harm to environment. In this work, a series of highly active solid acid catalysts HPW/MCM-41 is prepared by impregnation method for the cyclopropanation of dicyclopentadiene. The composition, structural and acidity of catalyst were characterized by TEM, XRD, NH 3 -TPD, etc. The 5 % HPW/MCM-41 contains more Dawson-type P 2 W 18 (H 6 P 2 W 18 O 62 ) and defective-type P 2 W 21 (H 6 P 2 W 21 O 71 ) that can provide the most abundant acid sites. This catalyst shows the best catalytic activity, the conversion and bicyclic product selectivity for cyclopropanation of dicyclopentadiene are 93.4 % and 55.7 %, respectively, both higher than that of CF 3 COOH. Moreover, such catalyst shows good catalytic activity for several olefin substrates, and can be recycled in several runs. This work provides a green and efficient catalyst for cyclopropanation reactions for synthesis of high-energy–density fuel, pesticide and medicine.
研究领域:
催化化学
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能源化学
·
环境科学
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产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Wei Wang,Zhensheng Shen,Jiaxiang Zhang,Lun Pan,Chengxiang Shi,Xiangwen Zhang,Ji-Jun Zou
High-energy–density fuels play a vital role in the development of the aviation industry because they can provide more propulsion energy than conventional liquid fuels. Constructing more five- or six-membered rings in fuel molecules is an efficient way to increase fuel density. However, as the number of rings increases, the hydrogen content of fuel molecules gradually decreases, resulting in a decrease in the mass calorific value, which limits the further improvement of the volumetric calorific value, meanwhile, the low-temperature characteristics of the fuel become worsen. Considering the high strain energy stored in cyclopropane moiety and the good cryogenic properties of spiro fuel, in this work, two spirocyclopropane high-energy–density fuels have been synthesized from cyclopentadiene by phase transfer catalytic cyclopropanation and palladium catalytic cyclopropanation, and the reaction conditions have been optimized. The synthesized fuels possess heat value and specific impulse higher than the widely used high-energy–density fuel JP-10. Additionally, their kinematic viscosity at low temperatures is only about one-third that of JP-10. The outstanding properties of the synthesized strained fuels suggest their good potential as high-energy–density fuels.
研究领域:
化学
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材料科学
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航空航天工程
·
燃料技术
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产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2020
·
IF 4.982
Yakun Liu,Chi Ma,Chengxiang Shi,Lun Pan,Junjian Xie,Si Gong,Yong-Chao Zhang,Genkuo Nie,Xiangwen Zhang,Ji-Jun Zou
With the rapid development of spacecraft such as rocket, it is increasingly important to develop high-energy and sustainable fuels. Biofuels synthesized from biomass derivatives provide great convenience for sustainable development. In this work, we reported a route for synthesis of high-energy cyclopropane bio-kerosene by cyclopropanation of myrcene with zinc carbenoid. The reaction conditions including reaction time, reaction temperature, solvent and molar ratio were optimized. Finally, a tricyclic cyclopropane bio-kerosene was synthesized with 69.8% yield under optimum conditions (i.e. zinc carbenoid synthesis temperature of −15 °C, cyclopropanation temperature of 25 °C and solvent of dichloromethane). Importantly, this bio-kerosene possesses a high specific impulse of 328.25 s, much better than the commercial rocket kerosene RP-1, as well as a high net-heat-value of 43.4 MJ/kg and good low-temperature properties.
研究领域:
能源生物学
·
有机化学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2021
·
IF 6.609
Yakun Liu,Chengxiang Shi,Lun Pan,Xiangwen Zhang,Ji-Jun Zou
With the rapid development of aerospace industry, it is significantly necessary to develop advanced rocket fuels with high density, high specific impulse and good combustion performance. In this work, we report the synthesis of cyclopropanated pinanes through cyclopropanation of pinene. The reaction conditions including reaction time, solvent type, halohydrocarbon and molar ratio of zinc carbenoid to pinene were optimized. The basic physical properties of fuel, including density, kinematic viscosity, freezing point, calorific value, and combustion performance were tested, and the specific impulses of cyclopropanated pinanes were also calculated. Importantly, the cyclopropanated α- and β-pinane possess high density of 0.90 and 0.91 g/mL, specific impulse of 330.58 and 330.39 s, which results in higher volumetric specific impulse than reported rocket fuels. They also show good low-temperature performance and better ignition and combustion performance than JP-10. These excellent performances indicate that the cyclopropanated α- and β-pinane have great application prospect as high-energy rocket fuel.
研究领域:
燃料化学
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航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Xinyue Zhang,Yuan Yao,Yingying Cao,Xin Tan,Xiaomin Fang,Yanqiang Zhang
The high strain energy of the three-membered ring can increase the combustion calorific value of space fuels. At present, the cyclopropanation of alkenes is the bottleneck to obtain highly-energy three-member-ring fuels. In this article, Pd single-site catalysts (SSCs) were prepared to catalyze the cyclopropanation of norbornene. Pd2+ on the SSCs enhanced the adsorption of CH2N2 through electrostatic interaction, efficiently forming metal carbene. The conversion and selectivity of norbornene cyclopropanation reached 99.9% and 96.9%, which are much higher than those of commercial Pd/C (conversion 42.3%, selectivity 80.8%). In addition, the obtained tricyclooctane shows excellent properties (density 0.93 g/cm3, calorific value 42.75 MJ/kg) to be a promising high-performance rocket fuel. This work provides an efficient method for the synthesis of cyclopropane-based space fuels from alkenes.
研究领域:
化学
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材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2023
·
IF 4.3
Zhang Hao-Tian,Niu Ming-Xin,Zhang Qi,Hu Chen-Yang,Pang Xuan
Isothiourea is an important class of sulfur-containing molecules showing unique catalytic and biological activities. As such, polyisothiourea is envisioned to be an interesting type of polymer that potentially exhibits a number of interesting properties. However, there is no access to synthesizing well-defined polyisothiourea, and currently isothiourea-containing polymers are mainly prepared by immobilizing onto other polymer’s side chain. Herein, we report the first facile synthesis of polyisothioureas via alternating copolymerization of aziridines and isothiocayanates. Mediated by the catalytic system of phosphazene superbases/alcohol, a broad scope of aziridines and isothiocayanates could be transformed into polyisothioureas with adjustable substitutions (11 examples). The structures of obtained polyisothioureas were fully characterized with 1 H-NMR, 13 C-NMR, and 1 H- 13 C HMBC NMR. Moreover, the polyisothioureas show tunable thermal properties depending on substitutions on the isothiourea linkages. The novel structure of these polyisothioureas will enable a powerful platform for the discovery of next-generation functional plastics.
研究领域:
高分子化学
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材料科学
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 41
·19857-19862
·
IF 3.925
Huifang Ma,Jie Liang,Keyume Ablajan
An efficient methodology was developed for the synthesis of multisubstituted spirocyclopropane derivatives. The reaction between isatin (acenaphthoquinone) and α-bromo(chloro)-acetophenone compounds afforded the corresponding spirocyclopropane products with high stereoselectivity via a one-pot tandem reaction in the presence of α-picoline and triethylamine. In addition, spirocyclopropanepyrazoles were obtained in good yields via a one-pot cascade reaction of α-bromo-acetophenone, pyrazolone and aromatic aldehydes. Diverse spirocyclopropane compounds were prepared through the multicomponent one-pot pathway. The high efficiency of this process and operational simplicity make it an attractive method for the synthesis of spirocyclopropanes.
研究领域:
有机化学
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药物化学
✓ 已验证
DOI
高影响因子
TETRAHEDRON
·
2024
·
IF 2.1
Ling-Juan Tang,Shun-Jun Ji,Zhong-Jian Cai
The monofluoroalkenes are found widespread applications in areas such as bioactive molecules, materials science and synthetic organic chemistry, therefore, investigating efficient methodologies to construct monofluoroalkenes is still in demand. In this paper, we reported an efficient synthesis of monofluoroalkenyl substituted pyranones/pyridones by using the gem -difluorocyclopropanes ( gem -DFCPs) as monofluoroalkenyl precursors. In the presence of Palladium catalyst, the monofluoroalkenyl group was introduced into the C3 positions of pyranones/pyridones successfully. The reaction was featured with high regioselectivity, mild conditions, broad substrate scope, easy to scale up synthesis, which provided a novel avenue for the late-stagy modification of pyranones/pyridones.
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2021
·
IF 5.909
Yu-Nong Li,Qi-Neng Xu,Lei-Feng Wu,Yao-Hui Guo,Huan Yue,Jun Zhou,Chang-Lei Ge,Hao-Ran Chang
On the basis of a synergistic strategy for CO 2 activation and conversion, a water-promoted selective synthesis of 5-aryl-2-oxazolidinones from aziridines and CO 2 has been exploited in a metal- and base-free system in confined nanospaces of hierarchical porous silica, affording moderate to good conversions and yields. In this process, carbonic acid in-situ generated interacts with and ingeniously activates the aziridine ring, facilitating its subsequent transformation and promoting the selectivity of 5-substituted products. DFT calculations , FTIR spectroscopy and pH value monitoring reveal that the excellent 5-postion regio-selectivity is dictated by kinetics, which is attributed to the formation of a latent benzyl carbocation in the transition state. The confined nanospaces of hierarchical porous silica can be considered as plenty of nanoreactors, which would change concentrations of reagents and activation parameters, stabilize transition states and enhance the kinetics process. This environment-friendly system provides a synergistic strategy of optimizing both the chemical function and physical microenvironment to enhance CO 2 activation, and enriches the carbon capture and utilization (CCU) coupling process by conversion of the waste (water-fixed CO 2 ) into value-added compounds.
研究领域:
化学工程
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材料科学
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环境科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Zhenzhong Li,Huating Jiang,Mingxiang Zhu,Fang Zhang
The development of heterogeneous chiral dirhodium catalysts for fabricating important bioactive substances and reducing the loss of noble metals has long been of significant interest. However, there still remains formidable synthetic challenges since it requires multiple steps of the synthetic process, and rhodium is easily leached from solid materials during the reaction. Here, we demonstrated a self-supported strategy based on the Suzuki–Miyaura coupling reaction to construct two chiral dirhodium organic frameworks for heterogeneous asymmetric catalysis. The synthetic approach is simple and efficient since it requires only a small number of preparation steps and does not require any catalyst supporting materials. The obtained chiral dirhodium materials can be highly efficient and recyclable heterogeneous catalysts for asymmetric cyclopropanation between diazooxindole and alkenes. Importantly, Rh2-MOCP-2 exhibited almost similar catalytic performance compared to homogeneous catalyst Rh2(S-Br-NTTL)4. The afforded catalytic performance (93.9% yield with 80.9% ee) highly surpasses previous heterogeneous dirhodium catalysts reported to date.
研究领域:
材料科学
·
有机化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL LETTERS
·
2012
·
IF 1.016
Meirong Liu,Shuhua Zhu,Jie Zhou
A new, sensitive, and simple HPLC method was described for the determination of 1-aminocyclopropane-1-carboxylic acid (ACC) in apple and peach extracts. The method was based on the derivatization of ACC with fluorescamine in borate buffer systems of pH 8.0 to yield a highly fluorescent product. The experimental parameters affecting the derivatization reaction efficiency were optimized by fluorimetric analysis. Under optimum derivatization conditions, the derivative product of ACC in apple and peach extracts without extra purification was successfully chromatographed on a C-18 column by HPLC coupled to fluorescence detection. The derivative product of ACC with fluorescamine could be well separated from other concomitant substances or their derivatives that might interfere with the determination of ACC. The linearity of ACC was measured in the range of 23.82–238.82 µg · L−1 with a good correlation coefficient of 0.9997. Based on signal-to-noise ratio of 3, a low detection limit of 5.0 µg · L−1 could be reached. The proposed method was applied successfully to the determination of ACC in the crude apple and peach extracts without extra purification with low RSDs of 0.19–1.9% and good recoveries of 90.89–104.4%. The sensitive HPLC quantitative method is of great significance for the investigations of ACC metabolism in plants.
研究领域:
植物学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
AICHE JOURNAL
·
2023
·Vol. 69
·期 7
·e18085
·
IF 3.7
Wei Wang,Baian Pu,Chi Ma,Chengxiang Shi,Lun Pan,Xiangwen Zhang,Ji-Jun Zou
Cyclopropane derivates are appealing to synthesis of high-energy-density fuels because of the high strained energy of the three-numbered ring. The catalytic cyclopropanation of olefin with diazomethane is very effective to construct the carbocycle. The majority of the catalysts employed are nonrecyclable homogeneous compounds. Herein, we report cyclopropanation of polycyclic olefins catalyzed by heterogeneous Pd/C. The optimal cyclopropanation conditions were explored utilizing dicyclopentadiene as model substrate and a series of polycyclic olefins were cyclopropanated with high yield. Additionally, the catalyst has good recyclability and stability, as shown by characterizations as well as the fact that no inactivation happens after cyclopropanation. The synthesized cyclopropane derivates exhibit good fuel characteristics like high density (1.006–1.087 g/cm 3 ), high volumetric net heat of combustion (42.58–46.45 kJ/cm 3 ), good low-temperature and combustion performance. This work shows industrial potential for cyclopropanation of polycyclic olefins with diazomethane.
研究领域:
化学工程
·
能源科学
·
催化材料
✓ 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）