- Hierarchical Micro- and Mesoporous Zn-Based Metal–Organic Frameworks Templated by Hydrogels: Their Use for Enzyme Immobilization and Catalysis of Knoevenagel Reaction
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Encapsulation of enzymes in metal–organic frameworks (MOFs) is often obstructed by the small size of the orifices typical of most reported MOFs, which prevent the passage of larger-size enzymes. Here, the preparation of hierarchical micro- and mesoporous
- Cheng, Kaipeng,Svec, Frantisek,Lv, Yongqin,Tan, Tianwei
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- The Photophysics of Three Naphthylmethylene Malononitriles
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The solvent dependence of the photophysical properties of three naphthylmethylene malononitriles, 1-(1-naphthalenylmethylene)-propanedinitrile (1-MN), 2-(2-naphthalenylmethylene)-propanedinitrile (2-MN), and 2-(3,4-dihydro-1(2H)-phenanthrenylidene)-propanedinitile (r2-MN), was studied in order to determine their potential utility as fluidity probes and to make comparisons to the better studied benzylidene malononitriles. Density functional calculations were used to understand the possible conformational states related to rotation about the vinyl-aromatic bond ("τ"). Absorption and emission frequencies, extinction coefficients, fluorescence quantum yields, and fluorescence lifetimes were measured in 11 representative solvents. Both the computational and experimental results indicate that the S0 → S1 transitions of these molecules have substantial charge-transfer character and produce highly polar excited states. Emission appears to result from relaxed S1 states which do not differ qualitatively from the Franck-Condon states reached by absorption. In 2-MN, time-resolved emission reveals the presence of two ground-state conformers ("a" and "b" differing by ~180 rotation about τ) coexisting in low-polarity solvents. In contrast, 1-MN appears to exist primarily as a single dominant ground-state conformer. Fluorescence lifetimes vary from ~1 ps in 1-MN to ~200 ps in 2-MN(a) at room temperature. With the exception of 2-MN(a), the lifetimes vary systematically with solvent in a manner similar to what is observed in the benzylidene malononitriles. Both solvent polarity and fluidity appear to be important determinants of lifetime. The primary mechanism of fluorescence decay in naphthylmethylene malononitriles is likely to be the same as that of the benzylidene malononitriles - twisting about the double bond in S1, which leads to rapid internal conversion via a conical intersection with S0. (Graph Presented).
- Breffke, Jens,Williams, Brian W.,Maroncelli, Mark
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- A green synthesis of a simple chemosensor that could instantly detect cyanide with high selectivity in aqueous solution
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A novel and simple cyanide chemosensor 2-(naphthalen-1-ylmethylene) malononitrile (L) was designed and synthesized via a green chemistry method in water without using any catalyst. The chemosensor showed an excellent sensitivity and selectivity for CN- in aqueous solution. The detection limit could be as low as 1.6 × 10-7 mol/L (0.16 μmol/L), which is far lower than the WHO guideline of 1.9 μmol/L cyanide for drink water.
- Lin, Qi,Chen, Pei,Fu, Yong-Peng,Zhang, You-Ming,Shi, Bing-Bing,Zhang, Peng,Wei, Tai-Bao
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- Direct fabrication of strong basic sites on ordered nanoporous materials: Exploring the possibility of metal-organic frameworks
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Heterogeneous strong base catalysts possessing ordered nanoporous structure are highly expected due to their high activity and shape selectivity in diverse reactions. However, their fabrication remains a great challenge because quite high temperatures (600-700 °C) are compulsory for the generation of strong basicity on conventional ordered nanoporous materials (i.e., zeolites and mesoporous silicas). Here, we report for the first time direct fabrication of strong basic sites on metal-organic frameworks (MOFs) by using guest-host redox (GHR) interaction between base precursors and low-valence metal centers (e.g., Cr3+), which breaks the tradition of thermo-induced decomposition of base precursors. It is fascinating that base precursor KNO3 can be converted to strong basic species on MIL-53(Cr) at 300 °C, which is much lower than that on zeolite Y (700 °C) and mesoporous silica SBA-15 (600 °C). The resultant solid base exhibits strong basicity, ordered nanoporous structure, and high activity and shape selectivity in base-catalyzed reactions.
- Liu, Wei,Zhu, Li,Jiang, Yao,Liu, Xiao-Qin,Sun, Lin-Bing
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- Halloysite nanotubes (HNTs)@ZIF-67 composites - A new type of heterogeneous catalyst for the Knoevenagel condensation reaction
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Composite materials based on metal-organic frameworks (MOFs) have shown outstanding performance due to their high porosity, molecular-level characterization, and structural and functional tunability. In this article, we develop a new type of composite material - HNTs@ZIF-67 - by the in situ growth of ZIF-67 nanoparticles (NPs) on halloysite nanotubes (HNTs), which were characterized by SEM, TEM, PXRD, FT-IR, TGA, XPS and N2 adsorption-desorption isotherms. The results clearly indicate that HNTs were wrapped in the ZIF-67 shell with a thickness of 50 nm which is much smaller than the 500 nm size of the as-synthesized ZIF-67. The nano-sized HNTs@ZIF-67 can effectively catalyze the Knoevenagel condensation reaction of larger conjugated/heterocyclic aromatic formaldehydes with malononitrile. The catalytic activities with >99% yields for the reaction of 4-pyridinecarboxaldehyde with malononitrile were maintained even after three cycles, and the composite still retained the original structure and morphology. This journal is
- Hou, Buwei,Wu, Jie
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- A novel adenine-based zinc(II) metal-organic framework featuring the Lewis basic sites for heterogeneous catalysis
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Metal-organic frameworks (MOFs), as a new sort of crystalline materials, have attracted lots of interest in many applications during the past decades. Recently, many efforts have been focused on the development of MOFs as heterogeneous catalysis. In this
- Zhang, Shixing,He, Hongming,Sun, Fuxing,Zhao, Nian,Du, Jianshi,Pan, Qinhe,Zhu, Guangshan
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- Impact of an aryl bulky group on a one-pot reaction of aldehyde with malononitrile and: N-substituted 2-cyanoacetamide
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In this study, we successfully explored the effect of steric hindrance on the one-pot reaction of different aryl aldehydes with malononitrile and N-substituted 2-cyanoacetamide in the presence of piperidinium acetate as the catalyst. It involved the Knoevenagel condensation of the aldehyde and malononitrile to produce arylidene malononitrile as an intermediate, which was further treated with N-substituted 2-cyanoacetamide to give 6-Amino-2-pyridone-3,5-dicarbonitrile derivatives when the less steric bulky group was involved. High steric hindrance changed the earlier reaction route and gave N-substituted 2-cyanoacrylamides via a slower route.
- Vala, Ruturajsinh M.,Patel, Divyang M.,Sharma, Mayank G.,Patel, Hitendra M.
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- Bifunctional design of stable metal-organic framework bearing triazole–carboxylate mixed ligand: Highly efficient heterogeneous catalyst for knoevenagel condensation reaction under mild conditions
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A highly water stable zinc metal–organic framework (ZnMOF), {[Zn(HL)2]}n, was synthesized using a triazole–carboxylate-based mixed ligand (L = 5-(4H-1,2,4-triazol-4-yl)isophthalic acid). A 2D MOF was formed by hydrothermal synthesis, and extended to a 3D supramolecular network through strong hydrogen bonding. This MOF was fully characterized by Fourier-transformation infrared spectroscopy, thermogravimetric analysis, single-crystal X-ray diffraction (XRD), powder XRD and elemental analysis. Owing to the d10 configuration of this ZnMOF, its luminescent properties were suitable for the sensing of the CN? ions over other anions, as inferred from the florescence result. However, regarding the catalytic mechanism, this ZnMOF showed a strong ability to react with CN?, which might be due to the hydrogen bonding between the COOH groups without coordination. This interaction behavior with CN? ions makes the ZnMOF a promising heterogeneous catalyst for Knoevenagel condensations using malononitrile and aldehyde derivatives as reactants under mild conditions. All reactions were conducted in water as a green solvent.
- Kumar, Sandeep,Li, Shuangshuang,Liu, Feixiong,Ren, Peng,You, Hengzhi,Zhao, Limin
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- Function-Structure Relationship in Metal-Organic Frameworks for Mild, Green, and Fast Catalytic C-C Bond Formation
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Tunability in chemical functionality is a promising characteristic of metal-organic frameworks (MOFs), which plays an important role in developing and improving the practical applications of MOFs. Here, we applied this important feature of MOFs to be in line with sustainable development and green chemistry principles through the synthesis of MOF-based heterogeneous organocatalysts. According to our green functionalization strategy, some isostructural MOFs (azine decorated TMU-4 with the formula [Zn(OBA)(BPDB)0.5]n·2DMF, azine-methyl functionalized TMU-5 with the formula [Zn(OBA)(BPDH)0.5]n·1.5DMF, dihydro-tetrazine decorated TMU-34 with the formula [Zn(OBA)(H2DPT)0.5]n·DMF, and tetrazine functionalized TMU-34(-2H) with the formula [Zn(OBA)(DPT)0.5]n·DMF, where H2OBA = 4,4′-oxybis(benzoic acid), BPDB = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene, BPDH = 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene, H2DPT = 3,6-di(pyridin-4-yl)-1,4-dihydro-1,2,4,5-tetrazine, and DPT = 3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine) have been applied for mild, green, and fast Knoevenagel condensation. These frameworks display different Lewis basic catalytic activities owing to their different functionality and function accessibility. Contrary to extensive articles published about Knoevenagel condensation, this study involves the rare examples in Knoevenagel condensation with such mild conditions (room temperature and atmospheric pressure) and with a green solution (water as the solvent). Due to the combined synergic effects of the Lewis basicity of TMU-frameworks, the amphoteric and hydrogen bond-participating nature of water molecules, maximum conversion times are reached just after 30 min (for TMU-5) and 60 min (for TMU-34). Stability and recyclability tests show that TMU-5 and TMU-34 are completely stable in water at reaction conditions and can retain their crystallinity, porosity, and functionality even after five cycles without any specific reduction in their catalytic conversion. Since, in many cases, amine decorated MOFs are applied in Knoevenagel catalyzed condensation, this study is beneficial in providing information about the effects of azine and tetrazine functional groups in reactant activation and the acceleration of Knoevenagel condensation.
- Razavi, Sayed Ali Akbar,Morsali, Ali
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- A covalent modification strategy for di-alkyne tagged metal-organic frameworks to access efficient heterogeneous catalysts toward C-C bond formation
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Organic and inorganic building blocks are used to construct a class of metal-organic frameworks (MOFs) that exhibit tremendous chemical tunability. In this study, a novel zirconium-based MOF UiO-66-(alkyne)2 with a di-alkyne tag was obtained through solvothermal pre-synthesis, which provides a potential covalent binding site for post-synthesis modification. On this basis, a gentle post-synthesis modification strategy based on covalency was expanded for introducing diverse metals, and a family of isostructural tailored materials (UiO-66-alkyne-Co, UiO-66-(alkyne-Co)2 and UiO-66-(alkyne-Ni)2) with base metals Ni or Co were designed and synthesized successfully. Among them, di-alkyne tagged UiO-66-(alkyne-Co)2 has shown unprecedented remarkable performance as a heterogeneous catalyst for the Knoevenagel reaction, completely converting benzaldehyde in just 5 min at room temperature, to our knowledge, faster than the reported MOF catalysts. Moreover, UiO-66-(alkyne-Co)2 maintains high stability and functionality after five cycles, and the catalytic activity is also preserved in the gram level scale-up experiment, indicating that UiO-66-(alkyne-Co)2 has great potential for practical application in the formation of C-C bonds. In a sense, this research provides an ideal platform for anchoring the required functional groups on alkyne-modified MOFs, which lays a foundation for finding more potential applications of MOF materials in the future.
- Liang, Qianqian,Cheng, Hua,Li, Chengwen,Ning, Liangmin,Shao, Liming
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p. 1210 - 1221
(2022/02/07)
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- MOFs assembled from C 3symmetric ligands: Structure, iodine capture and role as bifunctional catalysts towards the oxidation-Knoevenagel cascade reaction
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Three new NiII/CoII-metal organic frameworks were self-assembled by the reaction of C3 symmetric 1,3,5-tribenzoic acid (H3BTC) and 2,4,6-tris(4-pyridyl)-1,3,5-triazine (4-TPT) ligands and NiII/CoII salts under solvothermal conditions. Isomorphous MOF1 and MOF2 exhibit a 3D pillar-layer framework based on binuclear M2(OH)(COO)2 units connected by tritopic BTC3- and 4-TPT ligands with a novel (3,5)-connected topology net. MOF3 displays a 3-fold interpenetrated 3D network exhibiting a (3,4)-connected topology net. The porous MOF3 can reversibly take up I2. The activated MOFs contain both Lewis acid (NiII center) and basic (uncoordinated pyridyl or carboxylic groups) sites, and act as bifunctional acid-base catalysts. The catalytic measurements demonstrate that the activated MOF3 exhibits good activities for benzyl alcohol oxidation and the Knoevenagel reaction and can be recycled and reused for at least four cycles without losing its structural integrity and high catalytic activity. Thus, the catalytic properties for the oxidation-Knoevenagel cascade reaction have also been studied.
- Zhang, Ying-Ying,Liu, Qing,Zhang, Lin-Yan,Bao, Yu-Mei,Tan, Jing-Yi,Zhang, Na,Zhang, Jian-Yong,Liu, Zhen-Jiang
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p. 647 - 659
(2021/01/28)
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- A readily accessible porous organic polymer facilitates high-yielding Knoevenagel condensation at room temperature both in water and under solvent-free mechanochemical conditions
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A novel nitrogen-rich amorphous porous organic polymer has been synthesized using a microwave-assisted process. Its high chemical stability, reusability and poor solubility enable the use of the porous polymer as a metal-free heterogeneous catalyst for C–
- Sarma, Parishmita,Sarmah, Kashyap Kumar,Kakoti, Dharittri,Mahanta, Sanjeev Pran,Adassooriya, Nadeesh Madusanka,Nandi, Goutam,Das, Pranab Jyoti,Bu?ar, Dejan-Kre?imir,Thakuria, Ranjit
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- Ferrocene-Functionalized Dithiocarbamate Zinc(II) Complexes as Efficient Bifunctional Catalysts for the One-Pot Synthesis of Chromene and Imidazopyrimidine Derivatives via Knoevenagel Condensation Reaction
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Four new mononuclear/coordination polymeric (CP) zinc(II) complexes (1-4) of ferrocenyl/pyridyl-functionalized dithiocarbamate ligands, N-ferrocenylmethyl-N-butyl dithiocarbamate (L1), N-ferrocenylmethyl-N-ethylmorpholine dithiocarbamate (L2), N-ferroceny
- Anamika,Drew, Michael G. B.,Kumar, Kamlesh,Singh, Nanhai,Yadav, Chote Lal
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p. 6446 - 6462
(2021/05/31)
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- Kinetically Controllable Pd-Catalyzed Decarboxylation Enabled [5 + 2] and [3 + 2] Cycloaddition toward Carbocycles Featuring Quaternary Carbons
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A decarboxylative protocol has been developed toward a range of carbocycles. The key success is based on the use of a batch of newly designed cyclic carbonates as substrates that can provide carbon-carbon zwitterion intermediate under palladium catalysis.
- Yan, Biwei,Zuo, Linhong,Chang, Xiaowei,Liu, Teng,Cui, Manying,Liu, Yang,Sun, Haiyu,Chen, Weipeng,Guo, Wusheng
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supporting information
p. 351 - 357
(2021/01/26)
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- Nickel?alkyne?functionalized metal?organic frameworks: An efficient and reusable catalyst
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Electron-donating groups in the robust MOF motif are able to provide an excellent catalytic platform, therefore obtaining site-isolated metal sites. In this study, the terminal alkyne is firstly introduced into UiO-66-type metal-organic frameworks (UiO-66-alkyne). Herein, to further study the application potential of this material, a covalently bonded nickel catalyst based on the alkynyl-tagged UiO-66-alkyne has been prepared and afforded us unprecedented highly dispersed and highly efficient catalytic active species. Meanwhile, this nickel-contained catalyst method for joining metals provided an alternative pathway regarding catalyst designing. With UiO-66-alkyne-Ni, the heterogeneous transformation of homogeneous catalysts is realized. Using benzaldehyde and malononitrile as starting materials, we were able to catalyze the Knoevenagel condensation within 45 min under room temperature with yield (> 99 %). Moreover, the recovery rate of the UiO-66-alkyne-Ni also outperformed previous MOFs in both small-scale and gram-level reactions, which shows UiO-66-alkyne-Ni is a potential contributor to the subsequent industrialization.
- Chen, Huixin,Cheng, Hua,Li, Jilin,Li, Wei,Liao, Shengyun,Liu, Xin,Ning, Liangmin,Shao, Liming,Tang, Siyuan
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- A new porous organic polymer containing Tr?ger's base units: Evaluation of the catalytic activity in Knoevenagel condensation reaction
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The classic Tr?ger's base polymerization of a diamine and dimethoxymethane with trifluoroacetic acid as catalyst generated a Tr?ger's base-type polymer (TBP), which exhibited the absolute insolubility in a variety of organic solvents because of its highly aggregated model. A new porous organic polymer was obtained by a simple Tr?ger's base polymerization reaction between a diamine and formaldehyde in the form of acetal in the presence of trifluoroacetic acid as catalyst. Tr?ger's base-type polymer (TBP) resulted insoluble in a wide range of organic solvents due to its rigid and aromatic structure. TBP was characterized spectroscopically (FT-IR), thermally and morphologically. As result, a thermostable and amorphous polymer bearing pores ranging between 50 and 300 nm and macro-voids of up to 12 μm was obtained. Due to the insolubility of the TBP, it was tested as a metal-free heterogeneous catalyst in the Knoevenagel condensation reaction, showing a high efficiency. For this, the optimal catalyst load, reaction time and reuse of the catalyst were studied using benzaldehyde and malononitrile as substrates. Furthermore, aldehydes with variable chain sizes and ethyl cyanoacetate replacing malononitrile were tested as substrate with a high percent of conversion (97–99%).
- Coll, Deysma,Escalona, Néstor,Jessop, Ignacio A.,Martin-Trasanco, Rudy,Niebla, Vladimir,Ortiz, Pablo A.,Pérez, Edwin,Rodríguez-González, Fidel E.,Tagle, Luis H.,Terraza, Claudio A.,Tundidor-Camba, Alain,Velázquez-Tundidor, M. V.
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- A series of microporous and robust Ln-MOFs showing luminescence properties and catalytic performances towards Knoevenagel reactions
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A series of microporous Ln(iii)-based metal-organic frameworks (1-Ln) have been hydrothermally synthesized using 4,4′,4′′-nitrilotribenzoic acid (H3NTB). Single crystal X-ray diffraction analyses show that 1-Ln are isostructural and have 3D porous frameworks with remarkable stability and permanent porosity for Ar and CO2 adsorption. In addition, 1-Ln exhibit diverse photoluminescence emissions depending on the nature of lanthanide ions. More importantly, 1-Ln are further studied in the Knoevenagel reactions of benzaldehyde derivatives and malononitrile under solvent-free conditions, and it is found that 1-Tb shows the best catalytic activities (yields up to 99%), providing a unique example to differentiate the roles of Ln ions within the frameworks in catalyzing Knoevenagel reactions.
- Tian, Miaomiao,Zheng, Jun,Xue, Jintang,Pan, Xuze,Zhou, Dandan,Yao, Qingxia,Li, Yunwu,Duan, Wenzeng,Su, Jie,Huang, Xianqiang
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supporting information
p. 17785 - 17791
(2021/12/16)
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- One-pot oxidant-free dehydrogenation-Knoevenagel tandem reaction catalyzed by a recyclable magnetic base-metal bifunctional catalyst
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A new base-metal bifunctional catalyst NH-Pd(0)@MNP was prepared via a facile procedure and fully characterized. The as-prepared catalyst was used as an efficient relay catalyst for the one-pot oxidant-free dehydrogenation-Knoevenagel condensation tandem reaction from benzyl alcohol in H2O under mild conditions and generated benzalmalononitriles with yield up to 96%. Meanwhile, the catalyst could be easily recovered from the reaction system by an external magnetic field, and is reusable with little loss of activity up to 6 runs (5%).
- Yuan, Xiaofeng,Wan, Zijuan,Ning, Jinfeng,Zhang, Qiang,Luo, Jun
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- Effect of Substituents on the Crystal Structures, Optical Properties, and Catalytic Activity of Homoleptic Zn(II) and Cd(II) β-oxodithioester Complexes
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Five novel zinc(II) and cadmium(II) β-oxodithioester complexes, [Zn(L1)2] (1), [Zn(L2)2]n (2), [Zn(L3)2]n (3) [Cd(L1)2]n (4), [Cd(L2)2]n (5), with β-oxodithioester ligands, where L1 = 3-(methylthio)-1-(thiophen-2-yl)-3-thioxoprop-1-en-1-olate, L2 = 3-(methylthio)-1-(pyridin-3-yl)-3-thioxoprop-1-en-1-olate, and L3 = 3-(methylthio)-1-(pyridin-4-yl)-3-thioxoprop-1-en-1-olate, were synthesized and characterized by elemental analysis, IR, UV-vis, and NMR spectroscopy (1H and 13C{1H}). The solid-state structures of all complexes were ascertained by single-crystal X-ray crystallography. The β-oxodithioester ligands are bonded to Zn(II)/Cd(II) metal ions in an Oa§S and N chelating/chelating-bridging fashion leading to the formation of 1D (in 2-4) and 2D (in 5) coordination polymeric structures, but complex 1 was obtained as a discrete tetrahedral molecule. Complex 4 crystallizes in the C2 chiral space group and has been studied using circular dichroism (CD) spectroscopy. The multidimensional assemblies in these complexes are stabilized by many important noncovalent C-H···π(ZnOSC3, chelate), ?···?, C-H···?, and H···H interactions. The catalytic activities of 1-5 in reactions involving C-C and C-O bond formation have been studied, and the results indicated that complex 3 can be efficiently utilized as a heterogeneous bifunctional catalyst for the Knoevenagel condensation and multicomponent reactions to develop biologically important organic molecules. The luminescent properties of complexes were also studied. Interestingly, zinc complexes 1-3 showed strong lumniscent emission in the solid state, whereas cadmium complexes 4 and 5 exhibited bright luminescent emission in the solution phase. The semiconducting behavior of the complexes was studied by solid-state diffuse reflectance spectra (DRS), which showed optical band gaps in the range of 2.49-2.62 eV.
- Anamika,Drew, Michael G. B.,Kumar, Kamlesh,Rajput, Gunjan,Singh, Nanhai,Yadav, Chote Lal
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supporting information
(2020/09/09)
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- Photoelectrochemical and thermal characterization of aromatic hydrocarbons substituted with a dicyanovinyl unit
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Seven aromatic hydrocarbons bearing a dicyanovinyl unit were prepared to determine the relationship between both the number of aromatic rings and location of acceptor substituent on their thermal and optoelectronic properties. Additionally, the density functional theory calculations were performed. The obtained compounds showed temperatures of the beginning of thermal decomposition in the range of 137–289 °C, being above their respective melting points found between 88 and 248 °C. They were electrochemically active and showed quasi-reversible reduction process (except for 2-(phen-1-yl)methylene)malononitrile). Electrochemically estimated energy band gaps were below 3.0 eV, in the range of 2.10–2.50 eV. The absorption and emission spectra were recorded in CHCl3 and NMP and in solid state. All compounds strongly absorbed radiation with absorption maximum ranging from 307 to 454 nm ascribed to the intramolecular charge transfer between the donor and acceptor units. The aromatic hydrocarbons were luminescent in all investigated media and exhibited higher photoluminescence quantum yields in the solid state due to the aggregation induced emission phenomena. Electroluminescence ability of selected compounds was tested in a diode with guest-host configuration. Additionally, the selected compound together with a commercial N719 was applied in the dye-sensitized solar cell.
- Fabiańczyk, Aleksandra,Gnida, Pawe?,Kotowicz, Sonia,Kula, S?awomir,Ma?kowski, Sebastian,Ma?ecki, Jan Grzegorz,S?k, Danuta,Schab-Balcerzak, Ewa,Siwy, Mariola
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- Manganese-organic framework assembled by 5-((4′-(tetrazol-5″-yl)benzyl)oxy)isophthalic acid: A solvent-free catalyst for the formation of carbon–carbon bond
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A new three-dimensional manganese-based metal–organic framework Mn4L2(HL)(H2O)5, (1), based on semi-rigid 5-((4′-(tetrazol-5′’-yl)benzyl)oxy)isophthalic acid ligand (H3L) have been prepared and charac
- Jiang, Yansong,Xu, Jianing,Zhu, Ziqian,Jiang, Changwei,Ma, Lin,Wang, Hui,Wang, Li,Fan, Yong
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- Synthesis, in vitro and in silico screening of 2-amino-4-aryl-6-(phenylthio) pyridine-3,5-dicarbonitriles as novel α-glucosidase inhibitors
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Inhibition of α-glucosidase enzyme is of prime importance for the treatment of diabetes mellitus (DM). Apart of many organic scaffolds, pyridine based compounds have previously been reported for wide range of bioactivities. The current study reports a series of pyridine based synthetic analogues for their α-glucosidase inhibitory potential assessed by in vitro, kinetics and in silico studies. For this purpose, 2-amino-4-aryl-6-(phenylthio)pyridine-3,5-dicarbonitriles 1–28 were synthesized and subjected to in vitro screening. Several analogs, including 1–3, 7, 9, 11–14, and 16 showed many folds increased inhibitory potential in comparison to the standard acarbose (IC50 = 750 ± 10 μM). Interestingly, compound 7 (IC50 = 55.6 ± 0.3 μM) exhibited thirteen-folds greater inhibition strength than the standard acarbose. Kinetic studies on most potent molecule 7 revealed a competitive type inhibitory mechanism. In silico studies have been performed to examine the binding mode of ligand (compound 7) with the active site residues of α-glucosidase enzyme.
- Ali, Muhammad,Faramarzi, Mohammad Ali,Jabbar, Abdul,Khan, Khalid Mohammed,Larijani, Bagher,Mahdavi, Mohammad,Perveen, Shahnaz,Salar, Uzma,Shamim, Shahbaz,Taha, Muhammad
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- 2D Hybrid Architectures Constructed from Two Kinds of Polyoxovanadates as Efficient Heterogeneous Catalysts for Cyanosilylation and Knoevenagel Condensation
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The design of heterogeneous catalysts for highly efficient catalysis for cyanosilylation reactions and Knoevenagel condensations is greatly significant, due to the important application of their products in industry. Herein, five hybrid compounds construc
- An, Haiyan,Chang, Shenzhen,Hou, Yujiao,Zhang, Jie,Zhu, Qingshan
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p. 10578 - 10590
(2020/08/12)
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- Effecting structural diversity in a series of Co(ii)-organic frameworks by the interplay between rigidity of a dicarboxylate and flexibility of bis(tridentate) spanning ligands
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In a one-pot self-assembly reaction of Co(OAc)2·4H2O, thiophene-2,5-dicarboxylic acid (H2tdc) and four different bis(tridentate) polypyridyl spanning ligands under ambient conditions, a series of structurally diverse metal-organic frameworks has been synt
- Gogia, Alisha,Khullar, Sadhika,Laha, Biswajit,Mandal, Sanjay K.
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p. 12298 - 12310
(2020/10/02)
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- Radical Rearrangement of Aryl/Alkylidene Malononitriles via Aza Michael Addition/Decynoformylation/Addition Sequence: An Access to α-Aminonitriles and α-Aminoamides
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An efficient, safe, and environmentally friendly tertiary butyl hydrogen peroxide (TBHP)-mediated rearrangement of aryl/alkylidene malononitrile with anilines has been developed with in situ generation of HCN as the cyanide source for the synthesis of sub
- Bhoite, Shubhangi P.,Bansode, Ajay H.,Suryavanshi, Gurunath
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supporting information
p. 14858 - 14865
(2020/12/02)
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- Oxidative Olefination of Benzylamine with an Active Methylene Compound Mediated by Hypervalent Iodine (III)
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Hypervalent iodine-mediated oxidative olefination of amines with an active methylene compound provides a rapid gateway towards the formation of electrophilic alkenes under mild reaction conditions in good to excellent yields. This is an efficient protocol for the preparation of substituted electrophilic alkenes.
- Rupanawar, Bapurao D.,Veetil, Sruthi M.,Suryavanshi, Gurunath
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p. 6232 - 6239
(2019/11/05)
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- Periodic Mesoporous Organosilicas as Efficient Nanoreactors in Cascade Reactions Preparing Cyclopropanic Derivatives
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In this work, three organosilica precursors functionalized with carbamate moieties were synthesized by condensing of 3-isocyanatopropyltriethoxysilane and coupling regents of either hydroquinone (HQ), bisphenol A (BPA), or 1,1′-bi-2-naphthol (BN). These organosilica precursors were covalently bonded in the framework of periodic mesoporous organosilicas by co-condensation and hydrolysis with tetraethyl orthosilicate (TEOS) under hydrothermal treatment. The compositions and physical properties were characterized with FTIR, XRD, thermogravimetric/differential thermal analysis (TG/DTA), 29Si NMR, 13C NMR spectroscopies, SEM, TEM, and BET technologies. These characterizations suggest that three different structures were formed as the result of different sizes and compositions of the organosilica precursors. The three mesoporous organosilicas were applied as heterogeneous catalysts in the one-pot cascade Knoevenagel and Michael cyclopropanic reactions for the synthesis of cyclopropanic derivatives and showed excellent activity and selectivity. The highest conversion was obtained with mesoporous catalyst (MC)-HQ owing to its ordered mesostructure, highest surface area, and weakest stereo effect of the organic linking groups compared with MC-BAP and MC-BN. This methodology employed cheaper and more easily obtainable raw materials as reagents over the traditional alkene additive system and these heterogeneous catalysts exhibit superior performance and recyclability than typical homogeneous organic catalysts.
- Huo, Hang,Jiang, Yanqiu,Zhao, Tingting,Wang, Junlei,Li, Defeng,Xu, Xianzhu,Lin, Kaifeng
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p. 1496 - 1505
(2019/03/27)
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- A Zn based metal organic framework as a heterogeneous catalyst for C-C bond formation reactions
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Herein, we report the synthesis and application of a Zn-Bp-BTC MOF (Bp-4,4′-bipyridine; BTC-1,3,5-benzene tricarboxylic acid; MOF-metal organic framework) as a heterogeneous catalyst for mediating organic reactions. Initially, conditions were optimized for the Knoevenagel condensation reaction using Zn-Bp-BTC as a heterogeneous catalyst by varying the solvent, temperature and catalyst loading. Although the reaction proceeded at room temperature using methanol as the solvent, 60 °C offered the best yield in a shorter duration. Under optimized reaction conditions, a wide range of α,β-unsaturated dicyano compounds were prepared from the corresponding carbonyl precursor and malononitrile, the active methylene counterpart. Systematic investigation was also carried out to assess the role of the ligand and metal salt in the Knoevenagel condensation reaction. It was found that the Zn-Bp-BTC MOF catalyzed the reaction efficiently in comparison to its analogue Zn-BTC MOF and precursor Zn(NO3)2·6H2O. Finally, catalytic recycling and stability studies showed that the catalyst is able to mediate the reaction for up to five consecutive cycles without undergoing any significant chemical or morphological changes. Further, the catalyst was tested for its efficacy in a multi-component reaction (MCR). A MCR with the Zn-Bp-BTC MOF as the catalyst afforded good yields and there was no reaction in the absence of the catalyst. Similarly, the catalyst was tested for its efficiency in benzimidazole synthesis.
- Madasamy, Kanagaraj,Kumaraguru, Shanmugasundaram,Sankar, Velayutham,Mannathan, Subramaniyan,Kathiresan, Murugavel
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p. 3795 - 3800
(2019/03/05)
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- Janus Interphase Organic-Inorganic Hybrid Materials: Novel Water-Friendly Heterogeneous Catalysts
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In this work, amphiphilic silica-based Janus-type acid and base catalysts are introduced as heterogeneous analogues of surfactants. The new interphase organic-inorganic hybrid catalysts comprise of two different groups (?C8H17, ?Csu
- Vafaeezadeh, Majid,Breuninger, Paul,L?sch, Philipp,Wilhelm, Christian,Ernst, Stefan,Antonyuk, Sergiy,Thiel, Werner R.
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p. 2304 - 2312
(2019/04/17)
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- An Efficient and Reusable Multifunctional Composite Magnetic Nanocatalyst for Knoevenagel Condensation
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A range of multifunctional magnetic metal-organic framework nanomaterials consisting of various mass ratios of the metal-organic framework MIL-53(Fe) and magnetic SiO 2 @NiFe 2 O 4 nanoparticles were designed, prepared, ch
- Yao, Nan,Tan, Jin,Liu, Yang,Hu, Yu Lin
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supporting information
p. 699 - 702
(2019/03/26)
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- Two Hg(II)-based Macrocycles Offering Hydrogen Bonding Cavities: Influence of Cavity Structure on Heterogeneous Catalysis
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We present synthesis and characterization of two Hg-macrocycles offering H-bonding based cavities of varying dimensions. Both Hg-macrocycles illustrate noteworthy difference in their catalytic performance that has been related to their cavity structures.
- Pachisia, Sanya,Gupta, Rajeev
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p. 6039 - 6047
(2019/10/21)
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- Method used for preparing substituted 1, 3-malononitrile
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The invention belongs to the field of fine chemical product preparation and medicine intermediate synthesis, and relates to a method used for preparing substituted 1, 3-malononitrile. According to themethod, an aldehyde or a ketone and malononitrile are subjected to condensation reaction to prepare substituted 1, 3-malononitrile, wherein water is taken as a solvent, the aldehyde or the ketone andmalononitrile are subjected to Knoevenagel condensation under catalytic effect of zinc proline so as to obtain the corresponding substituted 1, 3-malononitrile. The method conditions are mild; operation is convenient; water is taken as a reaction solvent, so that the method is friendly to the environment; and the application prospect is promising.
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Paragraph 0032-0033
(2019/08/07)
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- Amino Acid Amide based Ionic Liquid as an Efficient Organo-Catalyst for Solvent-free Knoevenagel Condensation at Room Temperature
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Abstract: Ionic liquids of amino acid amide were synthesized and used as an efficient catalyst for solvent-free Knoevenagel condensation. Synthesized ionic liquids are an environmentally benign, inexpensive, metal free and plays the dual role of solvent as well as an efficient catalyst for Knoevenagel condensation. A wide range of aliphatic, aromatic and heteroaromatic aldehydes easily undergo condensation with malononitrile and ethyl cyanoacetate. The reaction proceeds at room temperature without using any organic solvent and is very fast with good to excellent yield. Additionally, the catalyst is easily separable and recyclable without loss of activity. Graphic Abstract: [Figure not available: see fulltext.].
- Burate, Pralhad A.,Javle, Balasaheb R.,Desale, Pranjal H.,Kinage, Anil K.
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p. 2368 - 2375
(2019/06/17)
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- Preparation of O-Protected Cyanohydrins by Aerobic Oxidation of α-Substituted Malononitriles in the Presence of Diarylphosphine Oxides
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A mild, reagent-cyanide-free, and efficient synthesis of O-phosphinoyl-protected cyanohydrins from readily available α-substituted malononitriles was realized using diarylphosphine oxides in the presence of O2. Mechanistic studies indicated that in addition to the initial aerobic oxidation of the malononitrile derivative notable features of this process include the formation of a tetrahedral intermediate and a subsequent intramolecular rearrangement. The phosphinoyl-protecting group can be removed by alcoholysis or by reduction with DIBAL-H.
- Zhang, Dapeng,Lian, Mingming,Liu, Jia,Tang, Shukun,Liu, Guangzhi,Ma, Cunfei,Meng, Qingwei,Peng, Haisheng,Zhu, Daling
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supporting information
p. 2597 - 2601
(2019/04/17)
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- Switching acidic and basic catalysis through supramolecular functionalization in a porous 3D covalent imine-based material
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Non-covalent inclusion of small acid and base molecules (CH3COOH and NEt3) in an imine structure based on micrometre COF-300 crystals and amorphous nanoparticles results in the facile modulation of their acid-base properties. Such a
- Luis-Barrerra, Javier,Cano, Rafael,Imani-Shakibaei, Ghazaleh,Heras-Domingo, Javier,Pérez-Carvajal, Javier,Imaz, Inhar,Maspoch, Daniel,Solans-Monfort, Xavier,Alemán, José,Mas-Ballesté, Rubén
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p. 6007 - 6014
(2019/11/14)
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- Postfunctionalized Metalloligand-Based Catenated Coordination Polymers: Syntheses, Structures, and Effect of Labile Sites on Catalysis
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In this work, pyridyl-appended Co3+ complexes (1 and 2) have been postfunctionalized by using 4-(bromomethyl)benzoic acid, thus changing the functionalities from pyridyl-N donors to carboxylate-O donors. Using two such postfunctionalized metalloligands (3 and 4), several homo and heterometallic coordination polymers (HCPs) have been synthesized. Single crystal structural analyses revealed that all HCPs presented intriguing one-dimensional catenated architectures. Postsynthetic modification induced flexibility was found to be responsible for the nearly identical architectures for two sets of HCPs starting from two different postfunctionalized metalloligands, 3 and 4. Two sets of HCPs differed by the presence (3a-3d) or absence (4a-4b) of labile coordinated water molecules that demonstrated a profound effect on the heterogeneous catalysis of Knoevenagel condensation reactions and cyanation reactions.
- Pandey, Saurabh,Kumar, Girijesh,Gupta, Rajeev
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p. 2723 - 2735
(2019/05/01)
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- Access to thiomorpholin-3-one derivatives: [3 + 3]-cycloadditions of α-chlorohydroxamates and 1,4-dithiane-2,5-diol
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A protocol of [3 + 3]-cycloaddition was proposed for the synthesis of 2H-1,4-thiazin-3(4H)-ones and thiomorpholine-3,5-diones from α-chlorohydroxamates and 1,4-dithiane-2,5-diol. This direct and practical method provides a novel and rapid approach for the
- He, Zhao-Lin,Chen, Yi,Wang, Xiaohua,Ni, Mingwang,Wang, Gang
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- Molybdenum carbide as an efficient and durable catalyst for aqueous Knoevenagel condensation
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By following green chemistry principles, various molybdenum compounds as cost-effective, commercially available, heterogeneous, and benign catalysts were used for the Knoevenagel condensation reaction. Among the compounds (Mo2C, MoS2, MoB, MoSi2), molybdenum carbide showed efficient performance for the Knoevenagel condensation in aqueous media at room temperature, affording the corresponding products in high yields within a short reaction time. Notably, using this commercially available heterogeneous catalyst, the deacetalization-Knoevenagel condensation of benzaldehyde dimethyl acetal and malononitrile at room temperature could successfully proceed in excellent yield. Molybdenum carbide could be recovered five times without loss of activity with an operationally simple procedure.
- Tavakolian, Mina,Najafpour, Mohammad Mahdi
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p. 16437 - 16440
(2019/11/11)
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- Rapid and efficient uncatalyzed knoevenagel condensations from binary mixture of ethanol and water
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This paper presents a new green protocol for Knoevenagel condensations of aldehydes and compounds with an active methylene group in a binary mixture of ethanol/water (3:7, v/v). This medium favored the uncatalyzed Knoevenagel reactions and easy workup pro
- Ferreira, Jo?o M. G. O.,De Resende Filho, Jo?o B. M.,Batista, Poliane K.,Teotonio, Ercules E. S.,Vale, Juliana A.
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p. 1382 - 1387
(2018/06/12)
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- Synthesis of Metallomacrocycle and Coordination Polymers with Pyridine-Based Amidocarboxylate Ligands and Their Catalytic Activities towards the Henry and Knoevenagel Reactions
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The reactions of 3,3′-{(pyridine-2,6-dicarbonyl)bis(azanediyl)}dibenzoic acid (H2L) with zinc(II), cadmium(II), and samarium(III) nitrates were studied, and the obtained compounds, [Zn(1κO:2κO′-L)(H2O)2]n (1), [
- Karmakar, Anirban,Rúbio, Guilherme M. D. M.,Guedes da Silva, M. Fátima C.,Pombeiro, Armando J. L.
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p. 865 - 877
(2018/12/10)
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- Nitrogen enriched polytriazine as a metal-free heterogeneous catalyst for the Knoevenagel reaction under mild conditions
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A nitrogen enriched (52 wt%) nanoporous polytriazine with a high specific surface area up to 850 m2 g-1 was synthesized by an ultra-fast (30 min reaction time) microwave assisted route using the inexpensive precursors cyanuric chlori
- Chaudhary, Monika,Mohanty, Paritosh
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supporting information
p. 12924 - 12928
(2018/08/01)
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- Bifunctional 2D Cd(II)-Based Metal-Organic Framework as Efficient Heterogeneous Catalyst for the Formation of C-C Bond
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A porous two-dimensional (2D) metal-organic framework (MOF), namely, [Cd(PBA)(DMF)]·DMF (Cd-PBA), has been solvothermally synthesized by the reaction of 5-(4-pyridin-3-yl-benzoylamino)-isophthalic acid ligand (H2PBA) and Cd(II) ions. Structural
- Hu, Lei,Hao, Gui-Xia,Luo, Hai-Dong,Ke, Chun-Xian,Shi, Guang,Lin, Jia,Lin, Xiao-Ming,Qazi, Umair Yaqub,Cai, Yue-Peng
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p. 2883 - 2889
(2018/05/09)
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- Defect engineering of highly stable lanthanide metal-organic frameworks by particle modulation for coating catalysis
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By virtue of their structural periodicity, tunability, high porosity and rich functionality, metal-organic frameworks (MOFs) are of great interest in catalysis. However, MOF crystals are fragile and difficult to use as robust adsorbents or catalysts witho
- Chen, Yifa,Zhang, Shenghan,Chen, Fan,Cao, Sijia,Cai, Ya,Li, Siqing,Ma, Hongwei,Ma, Xiaojie,Li, Pengfei,Huang, Xianqiang,Wang, Bo
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supporting information
p. 342 - 348
(2018/01/12)
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- An Amino-Functionalized Metal-Organic Framework, Based on a Rare Ba12(COO)18(NO3)2 Cluster, for Efficient C3/C2/C1 Separation and Preferential Catalytic Performance
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A barium(II) metal-organic framework (MOF) based on a predesigned amino-functionalized ligand, namely [Ba2(L)(DMF)(H2O)(NO3)1/3]?DMF?EtOH?2 H2O (UPC-33) [H3L=4,4′-((2-amino-5-carboxy-1,3-phenylene)bis(ethyne-2,1-diyl))dibenzoic acid] has been synthesized. UPC-33 is a 3-dimensional 3,18-connected network with fcu topology with a rare twelve-nuclear Ba12(COO)18(NO3)2 cluster. UPC-33 shows permanent porosity and a high adsorption heat of CO2 (49.92 kJ mol?1), which can be used as a platform for selective adsorption of CO2/CH4 (8.09). In addition, UPC-33 exhibits high separation selectivity for C3 light hydrocarbons with respect to CH4 (228.34, 151.40 for C3H6/CH4, C3H8/CH4 at 273k and 1 bar), as shown by single component gas sorption and selectivity calculations. Due to the existence of ?NH2 groups in the channels, UPC-33 can effectively catalyze Knoevenagel condensation reactions with high yield, and substrate size and electron dependency.
- Fan, Weidong,Wang, Yutong,Zhang, Qian,Kirchon, Angelo,Xiao, Zhenyu,Zhang, Liangliang,Dai, Fangna,Wang, Rongming,Sun, Daofeng
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p. 2137 - 2143
(2017/12/13)
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- Water assisted and choline chloride-dimethylurea deep eutectic salts as catalyst towards the attractive reaction of indole, benzaldehyde, and malononitrile
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The condensation of indole, benzaldehyde, and malononitrile was relatively rigorous compared with other Yonemitsu type reaction. We described a strategy using catalytic amount of choline chloride-dimethylurea deep eutectic salts as cheap and safe accelerator. We also found that introducing right amount of water in reaction system was crucial. This method tolerates variations in all three components to get desired 3-substituted indoles in satisfactory yields.
- Ruan, Hongli,Lv, Yue,Yu, Shijun,Lv, Chengwei,An, Yue
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p. 1266 - 1274
(2018/08/06)
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- A metalloligand appended with benzimidazole rings: Tetranuclear [CoZn3] and [CoCd3] complexes and their catalytic applications
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A novel Co3+-based metalloligand 1 offering appended benzimidazole rings has been prepared and utilized for the synthesis of tetranuclear [CoZn3] (2 and 2-Cl) and [CoCd3] (3) heterometallic coordination complexes (HCCs). C
- Pandey, Saurabh,Bansal, Deepak,Gupta, Rajeev
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p. 9847 - 9856
(2018/06/18)
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- Coordination driven self-assembly of [2 + 2 + 2] molecular squares: Synthesis, crystal structures, catalytic and luminescence properties
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The one-pot self-assembly of three components (metal acetates as the metal precursor, the tridentate polypyridyl ligand, N,N′-bis(2-pyridylmethyl)-tert-butylamine (bpta), as a capping ligand and bent dicarboxylic acids, 4,4′-(dimethylsilanediyl)bis-benzoi
- Gupta, Vijay,Mandal, Sanjay K.
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p. 9742 - 9754
(2018/08/06)
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- First organocatalytic asymmetric synthesis of 1-Benzamido-1,4-Dihydropyridine Derivatives
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Preliminary results concerning the first asymmetric synthesis of highly functionalized 1-benzamido-1,4-dihydropyridine derivatives via the reaction of hydrazones with alkylidenemalononitriles in the presence of β-isocupreidine catalyst are reported. The m
- Auria-Luna, Fernando,Marqués-López, Eugenia,Herrera, Raquel P.
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- Amino-functionalized MOFs with high physicochemical stability for efficient gas storage/separation, dye adsorption and catalytic performance
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A major goal of metal-organic framework (MOF) research is to adjust the structure and function for specific applications. It is highly desirable to develop new multifunctional MOF materials for selective guest molecule storage/separation and catalysis. Recent advances in the synthesis of MOFs have created new opportunities in this direction. Although many multifunctional MOFs have been synthesized to explore different applications, it is still a challenge to construct MOFs with high physicochemical stability for specific applications. In addition, most of the MOFs only have a microporous structure, which is not conducive to the transportation of substances and the entry of macromolecules, thus limiting the applications of these materials in macromolecular adsorption. Herein, we present three amino-functionalized InIII/AlIII/ZrIV-based MOFs with high physicochemical stability for multifunctional performances. The pore size of these MOFs varies from a few angstroms to the nanometre scale, and their specific surface areas and pore volumes gradually increase with the change of nodes. Further studies reveal that these MOFs are promising candidates as storage mediums for hydrogen (H2) and as separation agents for the selective removal of (C3Hn-C2Hn) from natural gas (NG). The mesoporous Zr-MOF can effectively enrich dye molecules to purify water, and the adsorption dynamics of a series of organic dyes shows that there are no size and charge-selective effects for the adsorption process. Furthermore, the catalytic efficiency and mechanism of Knoevenagel condensation reactions have also been studied in detail. Overall, the three versatile amino-functionalized MOFs highlight the advantages of metal-organic frameworks for designing host materials tailored for applications in hydrogen (H2) storage, light hydrocarbon adsorption/separation, water purification, and catalysis.
- Fan, Weidong,Wang, Xia,Xu, Ben,Wang, Yutong,Liu, Dandan,Zhang, Ming,Shang, Yizhu,Dai, Fangna,Zhang, Liangliang,Sun, Daofeng
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supporting information
p. 24486 - 24495
(2019/01/03)
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- Method for aldehyde Knoevenagel condensation reaction under conditions of no catalyst or solvent
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The invention discloses a method for an aldehyde Knoevenagel condensation reaction under conditions of no catalyst or solvent. In a glove box, aldehyde and malononitrile are sequentially added to a nuclear magnetic resonance tube, then, the glove box is m
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Paragraph 0100-0102
(2018/11/22)
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- Knoevenagel condensation reaction catalysed by Al-MOFs with CAU-1 and CAU-10-type structures
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The metal-organic frameworks (MOFs) CAU-1-NH2 ([Al4(OH)2(OCH3)4(p-BDC-NH2)3], (p-BDC-NH2)2- = 2-aminoterephthalate) and CAU-10-NH2 ([Al(OH)(m-BDC-NH2)], (m-BDC-NH2)2- = 5-aminoisophthalate) which possess two different pore sizes were studied for their catalytic activity as heterogeneous solid base catalysts in the Knoevenagel condensation reaction between benzaldehyde and malononitrile under mild reaction conditions (40 °C, 7 h, ethanol). For comparison, isoreticular MOFs containing a smaller amount of -NH2 groups (CAU-1-NH2/H) or no -NH2 groups (CAU-10-H) were synthesized. A two-step synthesis route including the synthesis of CAU-1-NH2 and its use as crystal seeds was developed to obtain the mixed-linker CAU-1-NH2/H compound. Only for CAU-1-NH2, up to 100% selectivity towards the desired Knoevenagel condensation product is observed. Hence, the catalytic activity of CAU-1-NH2 was tested between various benzaldehydes containing different substituents with malononitrile. By employing benzaldehyde and malononitrile as the starting materials, it is found that the mixed-linker MOF CAU-1-NH2/H catalyses the formation of the acetal (benzaldehyde diethyl acetal), while both CAU-10 materials lead to mixtures of the two products. Furthermore, the catalyst stability was also examined through reusability and leaching experiments and it is observed that the catalyst can be reused with no significant drop in its activity.
- Dhakshinamoorthy, Amarajothi,Heidenreich, Niclas,Lenzen, Dirk,Stock, Norbert
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p. 4187 - 4193
(2017/08/04)
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