- A Dynamic Three-Dimensional Covalent Organic Framework
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A guest-induced reversible crystal-structure transformation is identified in a new 3D covalent organic framework (COF) by comprehensive analyses using powder X-ray diffraction, organic vapor sorption isotherm, and 129Xe NMR spectroscopy. The revolving imine bond in interpenetrating 3D networks is uncovered as the key to the dynamic behavior, the potential applications of which are illustrated by gas separation and heterogeneous catalysis, thus paving the way to the design of stimuli-responsive and multifunctional COF materials.
- Ma, Yun-Xiang,Li, Zhi-Jun,Wei, Lei,Ding, San-Yuan,Zhang, Yue-Biao,Wang, Wei
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- Two Cu(II) coordination polymers: Heterogeneous catalytic Knoevenagel condensation reaction and treatment activity on atherosclerosis via regulating the expression of the COX-2 in vascular endothelial cells
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By altering auxiliary nitrogen-donor ligands, two novel coordination polymers (CPs) containing Cu(II) formulated as [Cu2.5(L)(trz)2(H2O)2]·2H2O (1) (Htrz = 1,2,4-triazole and H3L = 5-(4-car
- Zhao, Yong-Chang,Zhang, Yan,Jiang, De-Ying,Wang, Liang,Sun, Ping
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- A Stable Y(III)-Based Amide-Functionalized Metal-Organic Framework for Propane/Methane Separation and Knoevenagel Condensation
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Here, a Y(III)-based metal-organic framework, JLU-MOF112 {[Y3(μ3-O)2(μ3-OH)(H2O)2(BTCTBA)2]·2[(CH3)2NH2]·5DMF·C6H5Cl·4H2O}, has been successfully synthesized under solvothermal conditions. JLU-MOF112 was constructed with amide-functionalized tricarboxylate ligands and Y(III)-based infinite chains, where the Y3 repeating units are arranged in a trans order. The overall framework could be viewed as a novel (3,5)-connected net with two types of channels along the [100] and [010] directions. JLU-MOF112 possesses a large BET surface area (1553 m2 g-1), a permanent pore volume (0.67 cm3 g-1), and outstanding thermal and chemical stability, which give JLU-MOF112 potential for the purification of natural gas, especially the equimolar separation of C3H8/CH4 with a high selectivity of 176. In addition, benefiting from the amide functional groups as Br?nsted basic sites and the exposure of open metal sites as Lewis acid sites after activation, JLU-MOF112 can serve as a high-efficiency heterogeneous catalyst for Knoevenagel condensation by the reactions of malononitrile with benzaldehyde (yield of 98%, turnover number of 392, and turnover frequency of 3.27 min-1) and diverse aldehyde compounds. A rational mechanism was put forward that the Knoevenagel condensation was catalyzed by the synergistic effect of the Lewis acid sites and Br?nsted basic sites, engendering the polarization of the carbonyl groups and the deprotonation of the methylene groups for nucleophilic attack.
- Qiao, Junyi,Zhang, Borong,Yu, Xueyue,Zou, Xiaoqin,Liu, Xinyao,Zhang, Lirong,Liu, Yunling
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supporting information
p. 3708 - 3715
(2022/02/25)
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- Flexible thiourea linked covalent organic frameworks
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Exploring covalent organic frameworks with new linkages is regarded as an efficient method to modulate the corresponding properties, and a new linkage is essential to the progress of this field. Herein, condensation of 1,3,5-triformylphloroglucinol with 1,1′-(1,4-phenylene)bis(thiourea), 1,1′-(2,5-dimethyl-1,4-phenylene)bis(thiourea) or 1,1′-(3,3′-dimethyl-[1,1′-biphenyl]-4,4′-diyl)bis(thiourea) were applied to construct COFs with thiourea linkages for the first time.
- Ai, Wenying,Hu, Fujia,Li, Chunzhi,Ma, Baiwei,Mi, Liwei,Qiao, Huijie,Wang, Zhuo,Xu, Yimeng,Zhai, Lipeng,Zhang, Lin
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p. 7576 - 7580
(2021/11/17)
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- Development of an efficient, one-pot, multicomponent protocol for synthesis of 8-hydroxy-4-phenyl-1,2-dihydroquinoline derivatives
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A one-pot quick and efficient multicomponent reaction has been developed for the synthesis of a new series of functionalized 8-hydroxy-4-phenyl-1,2-dihydroquinoline derivatives using 30 mol% ammonium acetate in ethanol as solvent. This economical protocol
- Tabassum, Rukhsana,Ashfaq, Muhammad,Oku, Hiroyuki
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p. 534 - 547
(2020/12/04)
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- Three Resorcin[4]arene-Based Two-Dimensional Zn(II) Supramolecular Isomers Synthesized via a Structure-Directing Strategy for Knoevenagel Condensation
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Herein, in the presence of three structure-directing agents (SDAs), a family of imidazole-functionalized resorcin[4]arene-based coordination polymers (CPs), [Zn(TIC4R)(HCOO)]·HCOO·0.5DMF·1.5H2O (1), [Zn(TIC4R)(CN)]·HCOO·DMF·2.5H2O (2), and [Zn(TIC4R)(H2O)
- Wang, Fei-Fei,Liu, Ying-Ying,Pei, Wen-Yuan,Ma, Jian-Fang
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supporting information
p. 7329 - 7336
(2021/05/29)
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- Two new calix[4]resorcinarene-based coordination cages adjusted by metal ions for the Knoevenagel condensation reaction
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Two new calix[4]resorcinarene-based coordination cages, namely, [Zn4(TPC4R)(PDC)4]·2DMF·6H2O (1-Zn) and [In11(TPC4R)2(PDC)16(μ2-OH)2(H2O)2]·[(CH
- Lu, Bing-Bing,Ma, Jian-Fang,Pei, Wen-Yuan,Wang, Tianqi,Yang, Jin
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supporting information
p. 9942 - 9948
(2021/07/28)
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- Phosphine-Catalyzed (4 + 2) Annulation of δ-Sulfonamido-Substituted Enones with 1,1-Dicyanoalkenes: Synthesis of Piperidine Derivatives
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The δ-sulfonamido-substituted enones were employed as phosphine acceptor in phosphine-catalyzed (4 + 2) annulation of 1,1-dicyanoalkenes. They served as a four-membered synthon to react with 1,1-dicyanoalkenes under mild reaction conditions, producing pip
- Liu, Min,Zhou, Leijie,Shi, Wangyu,Hu, Yimin,Liao, Jianning,Duan, Zeqing,Wang, Wei,Wu, Yongjun,Zheng, Bing,Guo, Hongchao
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supporting information
p. 7703 - 7707
(2021/10/20)
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- Amides as surrogates of aldehydes for C-C bond formation: amide-based direct Knoevenagel-type condensation reaction and related reactions
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Aldehydes are perhaps the most versatile compounds that enable many C-C bond forming reactions, which are not amenable for other subclasses of carbonyl compounds. We report the first use of amides as surrogates of aldehydes for C-C bond formation, namely,
- Ou, Wei,Huang, Pei-Qiang
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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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- Synthesis, biological evaluation, and molecular modeling of nitrile-containing compounds: Exploring multiple activities as anti-Alzheimer agents
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Based on the monoamine oxidase (MAO) inhibition properties of aminoheterocycles with a carbonitrile group we have carried out a systematic exploration to discover new classes of carbonitriles endowed with dual MAO and AChE inhibitory activities, and Aβ anti-aggregating properties. Eighty-three nitrile-containing compounds, 13 of which are new, were synthesized and evaluated. in vitro screening revealed that 31, a new compound, presented the best lead for trifunctional inhibition against MAO A (0.34 μM), MAO B (0.26 μM), and AChE (52 μM), while 32 exhibited a lead for selective MAO A (0.12 μM) inhibition coupled to AChE (48 μM) inhibition. Computational analysis revealed that the malononitrile group can find an advantageous position with the aromatic cleft and FAD of MAO A or MAO B. However, the total binding energy can be handicapped by an internal penalty caused by twisting of the ligand molecule and subsequent disruption of the conjugation (32 in MAO B compared to the conjugated 31). Conjugation is also important for AChE as well as the hydrophilic character of malononitrile that allows this group to be in close contact with the aqueous environment as seen for 83. Although the effect of 31 and 32 against Aβ1–42, was very weak, the effect of 63 and 65, and of the new compound 75, indicated that these compounds were able to disaggregate Aβ1–42 fibrils. The most effective was 63, a (phenylhydrazinylidene)propanedinitrile derivative that also inhibited MAO A (1.65 μM), making it a potential lead for Alzheimer's disease application.
- Silva, Daniel,Mendes, Eduarda,Summers, Eleanor J.,Neca, Ana,Jacinto, Ana C.,Reis, Telma,Agostinho, Paula,Bolea, Irene,Jimeno, M. Luisa,Mateus, M. Luisa,Oliveira-Campos, Ana M. F.,Unzeta, Mercedes,Marco-Contelles, José,Majekova, Magdalena,Ramsay, Rona R.,Carreiras, M. Carmo
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p. 215 - 231
(2019/09/03)
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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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- Design, synthesis and biological evaluation of new series of hexahydroquinoline and fused quinoline derivatives as potent inhibitors of wild-type EGFR and mutant EGFR (L858R and T790M)
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New series of hexahydroquinoline and fused quinoline derivatives were designed and synthesized. The thirty seven new compounds were screened for in vitro antitumor activity against HepG2, HCT-116 and MCF-7 cancer cells. Results indicated that compounds 2e
- Shaheen, Mennatallah A.,El-Emam, Ali A.,El-Gohary, Nadia S.
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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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supporting information
p. 17621 - 17628
(2020/12/30)
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- 1,4,5,6,7,8-Hexahydroquinolines and 5,6,7,8-tetrahydronaphthalenes: A new class of antitumor agents targeting the colchicine binding site of tubulin
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New series of 2-amino-1,4,5,6,7,8-hexahydroquinoline-3-carbonitriles 3a,b and 2-amino-5,6,7,8-tetrahydronaphthalene-1,3-dicarbonitriles 4a-h were synthesized and evaluated for their antitumor activity. In vitro antitumor screening of the new members again
- Shaheen, Mennatallah A.,El-Emam, Ali A.,El-Gohary, Nadia S.
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supporting information
(2021/06/14)
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- Discrete coordination molecule container and preparation method and small molecule catalysis application thereof
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The invention relates to a discrete coordination molecule container and a preparation method and application thereof. The structure of the discrete coordination molecule container is [M4 (mu4-B) (X)]6Y6Z2, wherein M is a metal element; b is H2O (water); X is a thiacalix [4] arene ligand; Y is an asymmetric tricarboxylic acid ligand; and Z is a symmetric tricarboxylic acid ligand. The discrete coordination molecule container provided by the invention is provided with a functionally modified inner cavity, a specific nano inner cavity structure realizes enrichment of an organic reaction substrate and enhances contact with catalytic active sites, and meanwhile, an acidic active center of mu4-H2O and an alkaline active center of imino form an acid-base dual catalytic active center. The discrete coordination molecular container provided by the invention is used for homogeneous catalysis of Knoevenagel condensation reaction, and has efficient catalytic activity.
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Paragraph 0055-0057
(2020/04/02)
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- Calix[4]arene-based polyoxometalate organic-inorganic hybrid and coordination polymer as heterogeneous catalysts for azide-alkyne cycloaddition and Knoevenagel condensation reaction
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Based on a neutral pyridyl-functional calix[4]arene ligand (L = tetrakis [(3-pyridylmethyl)oxy]-p-tertbutylcalix[4]arene), one polyoxometalate-based organic-inorganic hybrid [Cu2L(SiW12O40)0.5]·CH3CN·
- Yue, Liu-Juan,Liu, Ying-Ying,Xu, Guo-Hai,Ma, Jian-Fang
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p. 15871 - 15878
(2019/10/22)
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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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- 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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- Fluorescent probe for detecting cyanide, and synthesis method and uses thereof
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The invention provides a fluorescent probe for detecting cyanide, and a synthesis method and uses thereof. The method comprises the following steps: mixing 2-naphthaldehyde, malononitrile and zinc chloride, heating to a melting state under a closed condition, and continuously stirring; after the reaction is finished, cooling to room temperature to obtain a crude product; washing the crude productwith aqueous ethanol and then performing suction filtration, and recrystallizing and drying the obtained filter cake to obtain the fluorescent probe. The probe molecule synthesized by the invention has the advantages of simple structure, low raw material cost, only one synthesis step, higher yield, and convenient large-scale production. In addition, the fluorescent probe has good practicability, can detect cyanide in different food samples, and has good application prospects in food detection.
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Paragraph 0033; 0037; 0038; 0040; 0041
(2019/02/21)
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- Hypervalent Iodine(III)-Catalyzed Epoxidation of β-Cyanostyrenes
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A convenient approach for the synthesis of β-cyanoepoxides is illustrated by iodine(III)-catalyzed epoxidation of electron-deficient β-cyanostyrenes, wherein the active catalytic iodine(III) species was generated in situ. The epoxidation of β-cyanostyrenes was performed using 10 molpercent PhI as precatalyst in the presence of 2.0 equivalents Oxone as an oxidant and 2.4 equivalents of TFA as an additive at room temperature under ultrasonic radiations. The β-cyanoepoxides were isolated in good to excellent yields in a short reaction time.
- Mangaonkar, Saeesh R.,Singh, Fateh V.
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p. 4473 - 4486
(2019/11/21)
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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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- Chiral-at-Metal Rh(III) Complex Catalyzed Cascade Reduction-Michael Addition Reaction
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An enantioselective three-component cascade reduction-Michael addition reaction catalyzed by chiral-at-metal Rh(III) complexes has been developed. With a Hantzsch ester as the hydride source, a number of malononitrile derivatives were prepared in good yie
- Wan, Qian,Li, Shiwu,Kang, Qiang,Yuan, Yaofeng,Du, Yu
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p. 15201 - 15211
(2019/11/19)
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- A multifunctional triazine-based nanoporous polymer as a versatile organocatalyst for CO2 utilization and C-C bond formation
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A triazine-based nanoporous multifunctional polymer with a SABET of 304 m2 g-1 has shown versatile catalytic activity in the conversion of CO2 to cyclic carbonates at 4 bar with almost 100% yield and selectivity, and in the conversion of CO2 to methanol and methane electrochemically. Additionally, it also catalyzes C-C bond formation via the Knoevenagel reaction.
- Sharma, Ruchi,Bansal, Ankushi,Ramachandran,Mohanty, Paritosh
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supporting information
p. 11607 - 11610
(2019/10/02)
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- Mercaptopyridine resorcinol calix [4] arene zinc complex as well as preparation method and application thereof
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The invention discloses a mercaptopyridine resorcinol calix [4] arene zinc complex and a preparation method thereof. The chemical formula of the complex is [Zn2(m-bdc)2(L)],8DMF.2CH3OH, wherein DMF represents N, N-dimethyl formamide. The preparation method comprises steps as follows: 0.04 mmol of Zn(NO3)2.6H2O with weight of 0.012 g, 0.04 mmol of isophthalic acid with weight of 0.007 g and 0.10 mmol of a ligand L with weight of 0.012 g are added to a reaction kettle, 5 mL of DMF and 3 mL of methanol are taken as reaction solvents, and all components are heated for 3 days at the temperature of100 DEG C. The complex has a layered structure and is high in synthetic repeatability and stable in product performance; as a heterogeneous catalyst, the complex has high catalytic efficiency; the complex can selectively detect Cr2O7 anions and Fe metal cations.
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Paragraph 0016; 0017
(2019/05/08)
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- Nmp-based ionic liquids: Recyclable catalysts for both hetero-Michael addition and Knoevenagel condensation in water
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A series of novel N-methyl piperidine (Nmp)-based ionic liquids with 1,2-propanediol group are synthesized and used as catalysts for both hetero-Michael addition of α,β-unsaturated amides and Knoevenagel condensation at room temperature in water; and all the examined substrates could be transformed into corresponding products in good to excellent yields. Meanwhile IL-catalyzed hetero-Michael addition of α,β-unsaturated amides in water has not been reported in the previous literatures. Additionally, the catalyst is recyclable for the two reactions. This finding provides a green catalyst for both hetero-Michael addition of α,β-unsaturated amides and Knoevenagel condensation in water.
- Yang, Pengkun,Liu, Yawei,Chai, Ling,Lai, Zhenzhen,Fang, Xiaomin,Liu, Baoying,Zhang, Wenkai,Lu, Minghua,Xu, Yuanqing,Xu, Hao
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supporting information
p. 1060 - 1067
(2018/05/23)
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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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- Knoevenagel reaction catalyzed by a reusable Br?nsted acid based on 1-alkyl-1, 2, 4-triazolium tetrafluoroborate
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The Knoevenagel reaction is one of the most useful methods for the synthesis of α, β- unsaturated nitriles. We disclose an efficient protocol for the Knoevenagel reaction of aldehydes with malononitrile catalyzed by 1-alkyl-1, 2, 4-triazolium salts to aff
- Kandasamy, Elango,Nagarajan, Sankaranarayanan,Shaikh, Tanveer M.
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supporting information
p. 133 - 138
(2018/03/06)
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- Ultrasound-assisted rapid synthesis of β-cyanoepoxides using hypervalent iodine reagents
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An elegant approach for the rapid synthesis of β-cyanoepoxides 3 by the epoxidation of β-cyanostyrenes 1 with PIDA 2a is described. The epoxidation of β-cyanostyrenes 1 was performed with 1.2 equiv. of PIDA 2a in MeCN-H2O (1:1) at room temperature in ultrasonic bath. The epoxidation reactions were completed in short reaction time and β-cyanoepoxides 3 were isolated in 69–94% yields.
- Singh, Fateh V.,Mangaonkar, Saeesh R.,Kole, Priyanka B.
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supporting information
p. 2169 - 2176
(2018/07/21)
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- One-pot synthesis of [1,2,4]Triazolo[1,5-a]pyridines from azines and benzylidenemalononitriles via copper-catalyzed tandem cyclization
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A simple and efficient copper-catalyzed tandem radical cyclization reaction has been discovered for the synthesis of triaryl [1,2,4]triazolo[1,5-a]pyridines from easily accessible azines and benzylidenmalononitriles. The new transformation involves multip
- Lv, Jianguang,He, Zhiqing,Zhang, Jianmin,Guo, Yuwei,Han, Ziwei,Bao, Xinhua
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supporting information
p. 3996 - 4004
(2018/06/20)
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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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- Efficient and Reusable Pb(II) Metal–Organic Framework for Knoevenagel Condensation
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A microporous lead–organic framework {[Pb4(μ8-MTB)2(H2O)4]·5DMF·H2O}n (MTB = methanetetrabenzoate, DMF = N,N′-dimethylformamide) was synthesized and studied as a catalyst in Knoevenagel condensation reactions. The framework is built from tetranuclear [Pb4(μ3-COO)(μ2-COO)6(COO)(H2O)4] clusters and exhibits a 3D structure, with repeated 1D jar-like cavities with sizes about 14.98 × 7.88 and 14.98 × 13.17??2 and BET specific surface area of 980?m2?g?1. To obtain open framework with unsaturated Pb(II) sites needed for catalysis, the thermal activation of the solvent exchanged sample was performed (DMF was exchanged by EtOH). The activated compound was tested in Knoevenagel condensation of bulky aldehydes and active methylene compounds at different temperatures. Excellent catalytic conversion and selectivity in condensation of small-sized aldehydes with malononitrile was observed, which indicates that the opened Pb(II) sites play a significant role in the heterogeneous catalytic process. Leaching test confirmed the stability of the catalyst in catalytic reactions. Moreover, the compound displayed good recyclability after several reuses without significant decrease in the original catalytic activity. Graphical Abstract: Novel Pb(II) metal–organic framework was tested in Knoevenagel condensation. The catalyst showed excellent catalytic conversion, selectivity and recyclability. Aldehydes with lower kinetic diameter demonstrated high conversions and yields. Catalyst is less efficient for condensation of larger aromatic aldehydes. [Figure not available: see fulltext.].
- Almá?i, Miroslav,Zeleňák, Vladimír,Opanasenko, Maksym V.,?ejka, Ji?í
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p. 2263 - 2273
(2018/07/05)
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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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- Heterogeneous ring-opening reactions and Knoevenagel condensation reactions with cobalt complexes: Effect of CoII versus CoIII states on catalysis
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This work illustrates comparative catalytic performance of two sets of cobalt complexes within a common macrocyclic ligand environment: CoII complexes 1 and 2 versus CoIII complexes 3 and 4. All four cobalt complexes functioned as the heterogeneous catalysts for the ring-opening reactions of assorted epoxides as well as Knoevenagel condensation reactions of assorted aldehydes. Cobalt(II) complexes were noted to be the superior catalysts over cobalt(III) complexes for both types of organic transformations. The observed difference in the catalytic performance of two sets of cobalt complexes has been related to the kinetic differences between CoII versus CoIII ions. All four cobalt complexes display high catalytic efficiency and excellent reusability without any apparent loss in the catalytic performance.
- Kumar, Sushil,Gupta, Rajeev
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p. 843 - 852
(2020/06/26)
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- Knoevenagel Condensation of Aldehydes and Ketones with Malononitrile Catalyzed by Amine Compounds-Tethered Fe3O4@SiO2 Nanoparticles
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Abstract: A new magnetic nanoparticle supported-catalyst was developed for the Knoevenagel condensation between malononitrile and several aldehydes. The Fe3O4@SiO2-3N (where 3N = N1-(3-trimethoxysilylpropyl)diet
- de Resende Filho, Jo?o Batista M.,Pires, Gilvan P.,de Oliveira Ferreira, Jo?o Marcos Gomes,Teotonio, Ercules E. S.,Vale, Juliana A.
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p. 167 - 180
(2017/02/10)
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- Poly(N-isopropylacrylamide-co-l-proline)-catalyzed Claisen-Schmidt and Knoevenagel condensations: Unexpected enhanced catalytic activity of the polymer catalyst
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The polymer catalyst is more effective than the corresponding monomer catalyst? Yes! The proline-modified polymer, poly(N-isopropylacrylamide-co-l-proline), was unexpectedly found to be more effective than the corresponding monomer l-proline catalyst in Claisen-Schmidt and Knoevenagel condensation reactions. 1H NMR, GC analysis and control reactions revealed that this abnormal phenomenon might be attributed to an enhanced concentration of the reactant on the surface of the polymer catalyst, which might be due to adsorption of the reactants to the polymer through hydrogen-bonding of the proline moiety with the reactants. This new polymer catalyst was so robust that it could be reused at least 10 times without deactivation. The polymer-catalyzed method was rather tolerant of substrates bearing sensitive groups that are usually incompatible with conventional acid- or base-catalyzed methods, reducing the protection-deprotection steps of the substrates.
- Zhang, Hao,Han, Mengting,Chen, Tian,Xu, Lin,Yu, Lei
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p. 48214 - 48221
(2017/11/03)
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- A Stable Porphyrin-Based Porous mog Metal-Organic Framework as an Efficient Solvent-Free Catalyst for C-C Bond Formation
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We herein report the porous 4-fold interpenetrated mog (moganite) metal-organic framework (MOF) [Cd3(tipp)(bpdc)2]·DMA·9H2O (1·Cd; H2tipp = 5,10,15,20-tetrakis(4-(imidazol-1-yl)phenyl)porphyrin, H2bpd
- Jiang, Wei,Yang, Jin,Liu, Ying-Ying,Song, Shu-Yan,Ma, Jian-Fang
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supporting information
p. 3036 - 3043
(2017/03/14)
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- N-heterocyclic carbene-promoted [3+2] cycloaddition of allenyl sulfone and arylidenemalononitriles
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N-Heterocyclic carbenes promote the [3+2] cycloaddition of allenyl sulfone and arylidenemalononitriles, accompanied by 1,2-migration of the sulfonyl group. This reaction provides a new route to highly substituted cyclopentenes.
- Kuwano, Satoru,Masuda, Toshinobu,Yamaguchi, Koki,Arai, Takayoshi
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p. 232 - 242
(2017/07/28)
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- Molecular modeling of drug-pathophysiological Mtb protein targets: Synthesis of some 2-thioxo-1, 3-thiazolidin-4-one derivatives as anti-tubercular agents
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Twenty novel 2-thioxo-1, 3-thiazolidin-4-one derivatives (5a-5t) were synthesized and evaluated for their antitubercular activity. The structure of the compounds was confirmed by IR, NMR and Mass Spectroscopy methods. In addition, single-crystal X-ray diffraction was performed for compound 5a. All the synthesized compounds were screened for their in-vitro antimycobacterial activity against MTB (H37RV, ATCC No: 27294) by Alamar Blue assay method. Compounds 5r, 5k, 5t displayed most potent in-vitro activity with MICs of 0.05, 0.1, 0.2 μg/ml concentrations respectively which are comparatively potent than the standards. Molecular docking and dynamics simulations were performed to find out the plausible mechanism of the titled compounds.
- Noorulla,Suresh, Ayyadurai Jerad,Devaraji, Vinod,Mathew, Bijo,Umesh, Devi
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p. 682 - 696
(2017/07/13)
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- A three dimensional association pyridine functional covalent organic framework material synthetic method
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The invention discloses a three-dimensional bipyridine functionalized covalent organic frame material (COF-LZU301) synthesis method which comprises following steps: (1) uniformly mixing tetra(4-anilino)methane in a tetrahedral configuration and linear 6-6'-diformyl-3,3'-bipyridine in an organic solvent; and (2) adding an acetic acid water solution as an acidic catalyst, and performing heating crystallization, centrifugal washing and heat drying to obtain the three-dimensional bipyridine functionalized covalent organic frame material (COF-LZU301). The COF-LZU301 has a three-dimensional diamond topological structure, regular and ordered porous and uniformly-distributed pyridine groups, so that the COF-LZU301 has excellent catalytic activity and shape selectivity for catalyzing a Knoevenagel reaction process. The COF-LZU301 achieves shape-selective catalysis of a typical alkali catalytic reaction.
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Paragraph 0031; 0041-0046
(2017/09/01)
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- Switching on Supramolecular Catalysis via Cavity Mediation and Electrostatic Regulation
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Synthetic supercontainers constructed from divalent metal ions, carboxylate linkers, and sulfonylcalix[4]arene-based container precursors exhibit great promise as enzyme mimics that function in organic solvents. The capacity of these artificial hosts to catalyze Knoevenagel condensation can be switched on when the aldehyde substrate possesses a molecular size and shape matching the nanocavity of the supercontainers. In contrast, little reactivity is observed for other aldehydes that do not match the binding pocket. This substrate-dependent catalytic selectivity is attributed to the Br?nsted acidity of the metal-bound water molecules located inside the nanocavity, which is amplified when the size/shape of the aldehyde substrate fits the binding cavity. The electrostatic environment of the binding cavity and the Br?nsted acidity of the supercontainer can be further modulated using tetraalkylammonium-based regulators, leading to higher reactivity for the otherwise unreactive aldehydes.
- Qiao, Yupu,Zhang, Long,Li, Jia,Lin, Wei,Wang, Zhenqiang
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supporting information
p. 12778 - 12782
(2016/10/04)
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- Microporous polyurethane material for size selective heterogeneous catalysis of the Knoevenagel reaction
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The first polyurethane material which is microporous (BET surface area of 312 m2 g-1) is prepared by solvothermal synthesis and acts as highly efficient and recyclable heterogeneous catalyst in the Knoevenagel condensation showing si
- Dey, Sandeep Kumar,De Sousa Amadeu, Nader,Janiak, Christoph
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supporting information
p. 7834 - 7837
(2016/07/06)
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- Cinchona alkaloid and di-: Tert -butyldicarbonate-DMAP promoted efficient synthesis of (E)-nitroolefins
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The synthesis of nitroolefins from aldehydes and olefins is generally limited by the formation of a mixture of cis and trans compounds. Here we report an alternative, metal-free protocol for the synthesis of β-nitroolefins from arylidinemalononitrile using cinchona alkaloid along with di-tert-butyldicarbonate-DMAP in high yields with total selectivity.
- Poomathi, Nataraj,Perumal, Paramasivan T.
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p. 54495 - 54502
(2016/07/06)
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- A carboxylate-rich metalloligand and its heterometallic coordination polymers: Syntheses, structures, topologies, and heterogeneous catalysis
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This work reports three heterometallic coordination polymers (HCPs), namely, [{(1′)2Zn8Na2(H2O)21}·20H2O]n (2), [{(1′)(1')Cd8(H2O)21}·32H2/
- Srivastava, Sumit,Kumar, Vijay,Gupta, Rajeev
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p. 2874 - 2886
(2016/06/01)
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- New porphyrazine macrocycles with high viscosity-sensitive fluorescence parameters
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New tetraaryltetracyanoporphyrazines have been obtained in the form of metal complexes and free bases via template assembly of a variety of aryltricyanoethylenes as structural units of the macrocycle, and photophysical properties of the products have been
- Lermontova,Grigoryev,Shilyagina, N. Yu.,Peskova,Balalaeva,Shirmanova,Klapshina
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p. 1330 - 1338
(2016/08/10)
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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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p. 9254 - 9267
(2015/08/04)
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- Fluorous bispidine: A bifunctional reagent for copper-catalyzed oxidation and knoevenagel condensation reactions in water
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Fluorous bispidine-type ligands have been developed to facilitate its recovery and reusability and to demonstrate its bifunctional property as a ligand and base in copper-catalyzed aerobic oxidation, the Knoevenagel condensation and tandem oxidation/Knoevenagel condensation in water under mild conditions. Application of the fluorous ligand was also extended to the surfactant-free copper-catalyzed allylic and benzylic sp3 C-H oxidation reaction in water. The fluorous ligands could be recovered using F-SPE with recovery ranging from 91-97% and could be reused five times with little loss of activity.
- Ang, Wei Jie,Chng, Yong Sheng,Lam, Yulin
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p. 81415 - 81428
(2015/10/06)
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- A metalloligand appended with thiazole rings: Heterometallic {Co3+-Zn2+} and {Co3+-Cd2+} complexes and their heterogeneous catalytic applications
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This work describes a Co3+-based metalloligand containing appended thiazole rings and its reactions with secondary metal ions to produce heterometallic {Co3+-Zn2+} and {Co3+-Cd2+} complexes. Structural studies show that some of the appended thiazole rings from the metalloligand coordinate to secondary metal ions, whereas the remaining ones act as hydrogen-bond acceptors to metal-bound CH3OH or H2O molecules. These heterometallic complexes function as reusable heterogeneous catalysts for the ring-opening reactions of epoxides as well as cyanation and Knoevenagel condensation reactions of aldehydes. The catalytic results illustrate that the microenvironment remains intact during the catalysis and potentially enhances the substrate interaction with the Lewis acidic secondary metal ions.
- Bansal, Deepak,Hundal, Geeta,Gupta, Rajeev
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p. 1022 - 1032
(2015/06/24)
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- Three-Dimensional Heterometallic Coordination Networks: Syntheses, Crystal Structures, Topologies, and Heterogeneous Catalysis
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This work presents the synthesis of {Co3+-Zn2+} and {Co3+-Cd2+} heterometallic coordination networks. These networks are originated from two unique Co3+-based metalloligands containing appended arylcarboxylic acid groups at the strategically placed positions. Such appended arylcarboxylate groups coordinate the secondary metal ions, Zn2+ and Cd2+, to afford distinct three-dimensional networks. All four networks display orderly arrangement of secondary metal ions and unique network topologies including an unprecedented one. These networks have been shown to act as the heterogeneous and reusable catalysts for the Knoevenagel condensation reactions and cyanation reactions of assorted aldehydes. Cyanation reactions nicely demonstrate the substrate size-exclusion catalysis.
- Srivastava, Sumit,Aggarwal, Himanshu,Gupta, Rajeev
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p. 4110 - 4122
(2015/08/18)
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