Green Chemical Engineering
·
2021
·
IF 0
Jiajun Wang,Zewei Liu,Shiye Li,Chaoping Li,Su Liu,Jingwen Feng,Rong Tan
Intramolecular acid-base cooperative catalysis is a powerful strategy to promote the nucleophilic additions in synthetic chemistry, since both substrates and nucleophiles can be activated simultaneously, yielding a lower energy reaction pathway. However, the systems often suffer from catalyst quenching due to the mutual neutralization of acid/base sites. Herein, we doped the boron (B) atoms in the tri- s -triazine ring of graphite-like carbon nitride ( g -C 3 N 4 ) framework, to develop the acid-base cooperative catalyst for nucleophilic addition. Characterization results demonstrated a foam-like hierarchical porous structure, as well as the coexistence of Lewis acid and base sites in the as-synthesized samples. As a result, the B-doped g -C 3 N 4 acted as the efficient acid-base cooperative catalysts, significantly promoting the Knoevenagel condensation whose key step involves in nucleophilic addition. A wide range of α, β-unsaturated carbonyl compounds with remarkably high yields (> 90%) was achieved even within 1 h in water, whereas the acid-free or base-free counterpart was far less efficient. In addition, the bifunctional catalysts exhibited excellent reusability with simple treatment. The novel B-doped g -C 3 N 4 catalytic system offers several advantages, such as operational simplicity, mild reaction conditions, high efficiency, and facile reuse of catalyst. All these advantages make it a benign protocol from the sustainability point of view, and inspired us to design the other bifunctional cooperative catalysts for a wide range of sustainable industrial applications.
研究领域:
材料化学
·
催化化学
✓ 已验证
DOI
MATERIALS CHEMISTRY AND PHYSICS
·
2014
·
IF 2.129
Xiaodan Li,Xiaoyong Luo,Ming Liu,Qichao Ran,Yi Gu
Two model compounds, 3-Phenyl-3,4-dihydro-2H-1,3-benzoxazine (PA) and 6,8-dimethyl-3-(2,4,6-trimethyl-phenyl)-3,4-dihydro-2H-1,3-benzoxazine (s-PA), were successfully synthesized and purificated. Compared with PA, s-PA also catalyzed the polymerization of BADCy even though there was no phenolic hydroxyl in its final ring-opened structures. It was confirmed that the real mechanism of benzoxazine catalyzing the polymerization of cyanate ester is the nucleophilic addition reaction of the oxygen anion on ring-opened benzoxazine to the positively charged carbon atom on cyano group. The catalytic effect also contains the contribution from the phenolic hydroxyl, but it is a secondary factor.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Chemistry of Heterocyclic Compounds
·
2017
·Vol. 53
·期 1
·42-45
·
IF 0.865
Yu Xueying,Wang Kangnan,Cao Duxia,Wu Qianqian,Guan Ruifang,Xu Yongxiao,Sun Yatong,Liu Zhiqiang
A benzothiazolium salt containing carbazole group has been synthesized in a good yield via simple condensation reaction. Its photophysical properties and affinity for cyanide anion (tetrabutylammonium cyanide) have been investigated. The compound exhibited quick and well visible UV/Vis absorption and fluorescence responses to cyanide anion in MeCN, as the yellow color faded and the orange fluorescence disappeared. The in situ analysis by 1H NMR indicated that the cyanide anion was added to the C=N bond in the benzothiazolyl group.
研究领域:
分析化学
·
光化学
·
有机化学
✓ 已验证
DOI
高影响因子
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY
·
2025
·Vol. 61
·期 5
·872-880
·
IF 0.9
Tong Mengnan
A versatile, convenient, mild, and efficient method for the synthesis of N-benzoyloxyamines containing alkenone or allyl ester groups, starting from hydroxylamine derivatives, is developed and successfully extended to a broader range of tertiary amine analogs.
研究领域:
有机化学
·
药物化学
·
合成化学
·
生物医学化学
·
分子设计
✓ 已验证
DOI
高影响因子
DYES AND PIGMENTS
·
2019
·
IF 4.018
Jing Li,Yongkang Yue,Fangjun Huo,Caixia Yin
Based on our previous work, we modified the coumarin derivate with orthotopic pinacol which can promote the specificity of the probe toward Cysteine (Cys) via steric-hinerance effect to develop a new Cys specific ratiometric fluorescent probe with α , β -unsaturated ketone as the reaction site. The nucleophilic addition reaction between Cys and α , β -unsaturated ketone rearranged the conjugation system of the probe which induced the hypochromatic shift of the fluorescent emission. The probe features good water solubility and the detection process reaches equilibrium within 10 min. Notably, the fast response would provide better precision because of the oxidizable nature of Cys. The fluorescence ratio of the probe increased 9-fold after the reaction and the corresponding detection limit was calculated to be 14 μ M. Furthermore, bioimaging experiment results indicated that the probe could detect exogenous and endogenous Cys specifically through the ratiometric manner.
研究领域:
化学
·
生物化学
·
分子生物学
·
分析化学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2025
·
IF 7.7
Lei Wang,Jinning Fan,Shangcong Gu,Yan Zhang,Yan Huang,Guiyi Yang,Keyi Li,Songfang Zhao,Zhiqiang Liu,Duxia Cao
Pyrosulfite, a widely used food additive known for its dual functions as both a preservative and antioxidant, is extensively applied in various fields, including food preservation, and pharmaceutical industry. However, excessive use may pose potential risks to human health. Here, a near-infrared fluorescence probe, 4-(1-cyano-4-(4-(dimethylamino-phenyl)-buta-1,3-dienyl)-1-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)pyridinium, iodide, named CPB was first developed. It triggers a near-infrared fluorescence (700 nm) quenching reaction with pyrosulfite in almost pure buffered solution through nucleophilic addition of the C C bond. This probe was effectively used for the quantitative monitoring of pyrosulfite in various foods and living cells, demonstrating high sensitivity. A near-infrared ratiometric fluorescent detection system for pyrosulfite was then successfully constructed by combining CPB and 3-(7-diethylamino-2-oxo-2 H -chromen-3-yl)-2-pyridin-4-yl-acrylonitrile ( CPA ) fluorescent compound. The ratiometric fluorescent detection system of the hydrogel-encapsulated probes has been successfully employed for the quantitative analysis of pyrosulfite with high sensitivity (detection limit: 0.12 µM), being able to keenly capture minor concentration changes. The system equipped with the two probes has also shown potential applications in anti-counterfeit ink.
研究领域:
分析化学
·
食品科学
·
生物成像
·
材料科学
·
荧光传感
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yuyu Peng,Yina Jiang,Chunyan Wang,Kelei Pang,Xiwang Li,Xiaofeng Zhou,Zhengjie Wang
Surface-enhanced Raman scattering (SERS) technique has significant advantages in the detection of gaseous small molecules, but it still faces challenges such as low adsorption capacity of gaseous small molecules on the surface of the SERS substrate, and low detection sensitivity due to the small Raman scattering cross section. In this paper, a nucleophilic addition strategy based on Ag@Au@4-nitrophenylhydrazine (4-NPH) @zeolite imidazolium ester backbone material-8 (ZIF-8) is proposed for achieving highly sensitive SERS detection of gaseous acetone. The SERS sensing platform was constructed by synthesizing Ag@Au nanoparticles with a core-shell structure modified with 4-NPH as a Raman reporter molecule, which was then encapsulated in a ZIF-8 porous framework. The nucleophilic addition reaction mechanism between acetone and 4-NPH was systematically investigated using density-functional theory (DFT), which revealed the changes in Raman spectra of 4-NPH due to the reaction and provided a theoretical basis for the specific detection of acetone. In addition, the charge transfer effect of more adsorption sites between the reaction product and the nanogold surface further enhanced the SERS signal. The constructed SERS substrate was demonstrated to have a low relative standard deviation (RSD) as low as 4.8 % for the detection of gaseous acetone, which ensured high sensitivity and reliability, and could detect at a concentration of 100 ppb. The method's excellent immunity to interference in complex exhaled gases gives it the potential to be applied to the non-invasive diagnosis of diabetes, demonstrating significant clinical applications.
研究领域:
分析化学
·
纳米技术
·
光谱学
·
化学传感
·
理论化学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2013
·
IF 3.73
Deyang Kong,Qing Xia,Guoqiang Liu,Qingguo Huang,Junhe Lu
Covalent coupling to natural humic constituents comprises an important transformation pathway for anilinic pollutants in the environment. We systematically investigated the reactions of chlorine substituted anilines with catechol and syringic acid in horseradish peroxidase (HRP) catalyzed systems. It was demonstrated that although nucleophilic addition was the mechanism of covalent bonding to both catechol and syringic acid, chloroanilines coupled to the 2 humic constituents via slightly different pathways. 1,4-addition and 1,2-addition are involved to catechol and syringic acid, respectively. 1,4-addition showed empirical 2nd order kinetics and this pathway seemed to be more permanent than 1,2-addition. Stability experiments demonstrated that cross-coupling products with syringic acid could be easily released in acidic conditions. However, cross-coupling with catechol was relatively stable at similar conditions. Thus, the environmental behavior and bioavailability of the coupling products should be carefully assessed.
研究领域:
环境化学
·
有机化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2015
·Vol. 4
·期 2
·383-390
·
IF 4.696
Xiaodong Yang,Xiuli Chen,Xiaodan Lu,Chenggong Yan,Yikai Xu,Xiaodong Hang,Jinqing Qu,Ruiyuan Liu
A novel fluorescence chemosensor 1 with aggregation-induced emission was designed and synthesized through a nucleophilic addition reaction between cyanide and triphenylamine. It exhibited remarkable selectivity and high sensitivity and was able to detect Fe3+, CN− and SO32− in almost pure aqueous solution with low detection limits of 1.44 μM, 9.88 nM and 0.107 μM, respectively. Job's plot and 1H NMR data showed that the binding stoichiometry of 1 with Fe3+, CN− or SO32− was 1 : 1. Further observations of 1H NMR titration suggested that a coordination bond was formed between two cyano of 1 and Fe3+ which resulted in fluorescence quenching of 1 after detection of Fe3+, whereas the nucleophilic addition of cyanide or sulfite to the vinyl group was responsible for the fluorescent quenching of CN− or SO32− toward 1. The biological applications of 1 were also evaluated and it was found to exhibit low cytotoxicity and membrane permeability. In addition, 1 could also be made into test strips to detect Fe3+ and CN− and was employed as a sensor for detection Fe3+ in living cells.
研究领域:
分析化学
·
材料科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Lixin Ma,Qian Xu,Limei Yin,Caixia Zou,Wei Wu,Chen Wang,Ruiyun Zhou,Zhiming Guo,Jianrong Cai
Fruits are susceptible to fungal infection and propagation during storage and transportation, and carry toxic metabolites of fungi. Patulin (PAT) is a primary mycotoxin contaminant in fruits and their products, with neurotoxicity, teratogenicity and carcinogenicity. The current chromatographic methods have limitations such as time-consuming, high-cost and the need for professional training. For rapid and sensitive detection of PAT, a surface-enhanced Raman scattering (SERS) method based on nucleophilic addition reaction was described in this paper. 4-aminothiophenol (4-ATP), silver ion, and cysteine (Cys) were successively attached to the surface of the Au-core-Ag-shell nanoparticles to form SERS sensors. PAT reacted with Cys to form a complex covering the surface of the sensor, attenuating the Raman signal from 4-ATP. Combined with the chemometrics algorithms, the hidden spectral information can be extracted effectively. Among these algorithms, the ant colony optimization partial least squares (ACO-PLS) model demonstrated the best predictive performance (R c = 0.9985, RMSEC = 0.0494). The recovery rate of PAT was 96.58 ∼ 101.74 % with the RSD ≤ 1.42 %. HPLC was used to verify the applicability of this SERS method, and the results indicated that the SERS method was consistent with the HPLC method ( p = 0.283 > 0.05). Furthermore, the SERS sensor was not subject to interference from ochratoxins A, alternariol, and the PAT structural analogues. Consequently, the proposed SERS sensor can realize rapid and highly selective detection of PAT, providing a new strategy for the rational design of SERS sensor based on chemical reaction for indirect detection of harmful substances.
研究领域:
分析化学
·
食品安全
·
光谱学
·
纳米技术
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
DESALINATION
·
2024
·
IF 8.3
Yuanyuan Yang,Guijing Chen,Ting Lei,Qingqing Qin,Shaowen Huang,Ming He,Shuhao Qin
Herein, a thin and high-potential loose nanofiltration (LNF) membrane was fabricated by one-step cross-linking with branched polyethyleneimine (PEI) using the reactive sites on the styrene maleic anhydride/chlorinated polyvinyl chloride membrane surface to for alkylation and nucleophilic addition reactions, respectively. As the molecular weight of branched PEI increased, the thickness of LNF membranes decreased and their pore sizes and surface potential increased (i. e., potential value of LNF membrane above 59 mV at pH = 7). Density functional theory calculations were used to understand the separation mechanism of LNF membranes. The rejection mechanisms of these membranes for Brilliant Blue R250, Methyl blue, Congo red, and Acid fuchsin were based on size-sieving, with rejection for all >95 %. However, the rejection mechanisms of Bromocresol green and Bromothymol blue were affected by the size-electrostatic synergy. Pleasingly, the NaCl rejection was <10 %. Furthermore, the 22 k-PEI-modified LNF membrane could not only effectively separate dye/NaCl under high pressure and high salinity but also maintain long-term stable desalination performance. Notably, the assessment of dye rejection in LNF membranes revealed that it is not solely based on the molecular weight of dye but is also related to the geometric shape of the organic substance.
研究领域:
材料科学
·
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2019
·
IF 4.914
Yaxuan Jing,Yu Xin,Yong Guo,Xiaohui Liu,Yanqin Wang
Aldol condensation is of significant importance for the production of fuel precursors from biomass-derived chemicals and has received increasing attention. Here we report a Nb 2 O 5 catalyst with excellent activity and stability in the aldol condensation of biomass-derived carbonyl molecules. It is found that in the aldol condensation of furfural with 4-heptanone, Nb 2 O 5 has obviously superior activity, which is not only better than that of other common solid acid catalysts (ZrO 2 and Al 2 O 3 ), more importantly, but also better than that of solid base catalysts (MgO, CaO, and magnesium-aluminum hydrotalcite). The detailed characterizations by N 2 sorption/desorption, NH 3 -TPD, Py-FTIR and DRIFTS study of acetone adsorption reveal that Nb 2 O 5 has a strong ability to activate the C=O bond in carbonyl molecules, which helps to generate a metal enolate intermediate and undergo the nucleophilic addition to form a new C–C bond. Furthermore, the applicability of Nb 2 O 5 to aldol condensation is extended to other biomass-derived carbonyl molecules and high yields of target fuel precursors are obtained. Finally, a multifunctional Pd/Nb 2 O 5 catalyst is prepared and successfully used in the one-pot synthesis of liquid alkanes from biomass-derived carbonyl molecules by combining the aldol condensation with the sequential hydrodeoxygenation .
研究领域:
催化
·
化学工程
·
可再生能源
·
有机化学
✓ 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）