- Black yet green: A?heterogenous carbon-based acid catalyst for the synthesis of biscyclic derivatives under eco-friendly conditions
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In this study, a simple, cost-efficient and green protocol has been described for the synthesis of biscoumarin and bisdimedone derivatives via one-pot Knoevenagel–Michael reaction of aromatic aldehydes with 4-hydroxycoumarin and dimedone, respectively. Th
- Teli, Pankaj,Sethiya, Ayushi,Agarwal, Shikha
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p. 731 - 750
(2021/12/09)
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- 2,2′-(Arylmethylene)bis(3-hydroxy-5,5-dimethylcyclohex-2-enone) crystals formation via atom economy reaction and their antioxidant activity
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Tetraketones with their diversified biological potencies became a highly significant class of oxygen-containing organic compounds. These are prepared by applying a simple Knoevenagel-Michael cascade procedure with 1,3-dicarbonyl compound and aldehydes. In
- Thakur, Deepa,Kaur, Manvinder,Malhi, Dharambeer Singh,Garg, Sonali,Sharma, Ajay,Sohal, Harvinder Singh
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p. 537 - 543
(2021/05/10)
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- Montmorillonite KSF-Catalyzed Synthesis of 2,2′-(Arylmethylene)bis(3-hydroxy-5,5-dimethylcyclohex-2-en-1-ones) for the Functionalization of MCM-41 Silica Nanoparticles
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Abstract: A green protocol has been developed for the preparation of 2,2′-(arylmethylene)bis(3-hydroxy-5,5-dimethylcyclohex-2-en-1-ones) following the multicomponent condensation reaction between aromatic alde-hydes and dimedone with excellent yields. The
- Mechi, L.,Mosbah, M. Ben,Moussaoui, Y.
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p. 1533 - 1539
(2021/10/26)
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- Green synthesis of tetraketones: crystal structure, DFT studies and Hirshfeld surface analysis of 2,2′-((3,4-dimethoxyphenyl) methylene) bis(3-hydroxy-5,5-dimethylcyclohex2-enone)
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The present work deals with a practically efficient protocol designed for the synthesis of tetraketones using ultrasound in the presence of boric acid as the catalyst. One of the tetraketone, (3a) was confirmed by crystallographic studies. The molecules i
- Shashi,Begum, Noor Shahina,Panday, Anoop Kumar
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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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- 1,8-Diazabicyclo [5.4.0] undec-7-ene functionalized cellulose nanofibers as an efficient and reusable nanocatalyst for the synthesis of tetraketones in aqueous medium
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Abstract: 1,8-Diazabicyclo [5.4.0] undec-7-ene functionalized cellulose nanofibers (CNF@DBU[Cl]) were simply prepared and characterized by analytical techniques. Scanning electron microscope confirmed that CNF@DBU[Cl] was formed with average size of 30–60?nm. X-ray diffraction of CNF@DBU[Cl] showed that the crystalline structure of the cellulose nanofibers was remained unchanged after functionalization. According to elemental analyses and thermal gravimetric analysis, the loading amount of organic group on cellulose nanofibers was found to be 1.46?mmol/g. The catalytic activity of DBU functionalized cellulose nanofibers was studied for the synthesis of biologically important tetraketone derivatives in the reaction of aldehydes with 1,3-dicarbonyl compounds. In the presence of CNF@DBU[Cl], the corresponding tetraketones were obtained in 80–96% yields under very mild reaction conditions. The catalyst was recovered and reused four successive runs without significant loss of catalytic activity. This method showed several significant advantages including short reaction times, high yields of products, use of various substrates, convenient work-up, no necessity of extraction or chromatographic purification steps, environmentally friendly conditions and lack of use of any harmful solvent. Graphic abstract: [Figure not available: see fulltext.].
- Lasemi, Zahra,Tajbakhsh, Mahmood,Alinezhad, Heshmatoallah,Mehrparvar, Forough
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p. 3667 - 3682
(2020/05/13)
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- Enhanced catalytic activity of bio-fabricated ZnO NPs prepared by ultrasound-assisted route for the synthesis of tetraketone and benzylidenemalonitrile in hydrotropic aqueous medium
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Abstract: Mushroom-like mesoporous and hexagonal ZnO nanoparticles were synthesized from plant extract and chemical method respectively, by co-precipitation method in aqueous medium. Different morphological forms of ZnO NPs were characterized by XRD, TGA, FESEM, EDX, FTIR, UV–Vis and BET. Neem (Azadirachta indica) leaf extract and ultrasound irradiation have a crucial role in the formation of different morphologies of ZnO NPs. ZnO NPs synthesized from plant extract and hydrotrope show a synergistic effect that leads to efficient synthesis of benzylidenemalonitrile and tetraketone derivatives at room temperature in water. Simple preparation of the catalyst, excellent yields, reusability of catalyst with consistent activity and ease of product isolation are the most significant advantages of this green protocol. Graphic abstract: [Figure not available: see fulltext.]
- Attar, Suraj R.,Kamble, Santosh B.,Shinde, Bipin
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- Selective synthesis of spiro and dispiro compounds using Mn(III)-based oxidation of tetracarbonyl compounds
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The Mn(III)-based oxidation of methylenebis(cyclohexanedione)s and methylenebis(piperidinedione)s as a tetracarbonyl compound was investigated under various conditions, selectively producing spiro dihydrofurans and dispiro cyclopropanes depending on the solvent. The mechanism for the formation of the spiro dihydrofurans and dispiro cyclopropanes was discussed. In addition, a simple synthesis of a new type of alkaloid, 3,4,6,7,8,10-hexahydro-1H-pyrano[3,2-c:5,6-c’]dipyridine-1,9(2H)-diones, was demonstrated.
- Hisano, Kazuki,Nishikawa, Satomi,Nishino, Hiroshi,Shibuya, Keisuke,Yokote, Suzuka
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supporting information
(2020/04/21)
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- Intercepted-Knoevenagel condensation for the synthesis of unsymmetrical fused-tricyclic 4H-pyrans
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4H-Pyrans (4H-Pys) and 1,4-dihydropyridines (1,4-DHPs) are important classes of heterocyclic scaffolds in medicinal chemistry. Herein, an indium(III)-catalyzed one-pot domino reaction for the synthesis of highly functionalized 4H-Pys, and a model of 1,4-D
- Shearer, Charles,Desaunay, Oriane,Zorc, Stephen,Richaud, Alexis D.,Samanta, Shyam S.,Jeedimalla, Nagalakshmi,Roche, Stéphane P.
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- Simple and efficient synthesis of 2,2′-arylmethylenebis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) derivatives
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Abstract: A simple and efficient method for the synthesis of 2,2′-arylmethylenebis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) derivatives using 4 ? molecular sieves as catalyst is described. This approach offers several advantages such as high yields, mi
- Magyar, ágnes,Hell, Zoltán
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p. 2021 - 2023
(2019/11/19)
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- Ni0 NPs anchored on acid-activated montmorillonite (Ni0-Mont) as a highly efficient and reusable nanocatalyst for synthesis of biscoumarins and bisdimedones
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Ni0 nanoparticles were immobilized on acid-activated montmorillonite (Ni0-Mont) by anchoring Ni(OAc)2·4H2O on modified micro/mesoporous montmorillonite followed by reduction with ethylene glycol. The prepared cl
- Rahmani, Soleiman,Zeynizadeh, Behzad
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p. 1227 - 1248
(2018/12/11)
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- An efficient synthesis of 2,2'-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) derivatives using Baker's yeast**
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A simple and efficient method was developed for the synthesis of 2,2'-arylmethylene dicyclohexane-1,3-dione derivatives via the Knoevenagel–Michael cascade reactions of aromatic aldehydes and 5,5-dimethyl-1,3-cyclohexanedione catalyzed by Saccharomyces ce
- Ashtarian, Jahanbakhsh,Heydari, Reza,Maghsoodlou, Malek-Taher,Yazdani-Elah-Abadi, Afshin
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p. 259 - 263
(2019/07/31)
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- Carbon-based nanocatalyst:?An efficient and recyclable heterogeneous catalyst for one-pot synthesis of gem-bisamides, hexahydroacridine-1,8-diones and 1,8-dioxo-octahydroxanthenes
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Abstract: In this abstract, we discuss the progress related to sulfonated carbon-based materials in various acid-catalyzed organic transformations which are then further utilized in medicinal field, laboratories and industries. A simple and novel methodol
- Kour, Jaspreet,Gupta, Monika,Chowhan, Bushra,Gupta, Vivek K.
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p. 2587 - 2612
(2019/07/23)
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- Nickel NPs @N-doped titania: an efficient and recyclable heterogeneous nanocatalytic system for one-pot synthesis of pyrano[2,3-d]pyrimidines and 1,8-dioxo-octahydroxanthenes
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Abstract: Catalysis holds a very important and promising place in chemical industry. In a typical chemical transformation, the use of a catalyst reduces the reagent-based waste and enhances the reaction selectivity, thereby minimizing the chances of getti
- Rajinder, Yogayta,Gupta, Monika,Kour, Jaspreet
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p. 1977 - 1992
(2019/04/30)
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- Anion functionalized ionic liquid from artificial sugar: A sustainable pathway for diverse bis-enol derivatives
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An artificial sugar saccharine based anion-functionalized ionic liquid [Bmim]Sac was synthesized and used for new and straightforward strategies for the construction of a diverse range of bis-enols. The advantage of this methodology is the use of a non-to
- Sharma, Himani,Srivastava, Suman
-
supporting information
p. 12054 - 12058
(2019/08/07)
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- Synthesis of Tetraketones Using ZnS Nanoparticles as an Efficient Catalyst
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An efficient pseudo-three-component synthesis of tetraketones is described by one-pot condensation of 5,5-dimethylcyclohexane-1,3-dione and aldehydes using ZnS nanoparticles at room temperature. This method provides several advantages such as mild reactio
- Safaei-Ghomi, Javad,Asadian, Saeedeh,Nazemzadeh, Seyed Hadi,Shahbazi-Alavi, Hossein
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p. 430 - 434
(2017/12/28)
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- Selective and highly efficient synthesis of xanthenedione or tetraketone derivatives catalyzed by ZnO nanorod-decorated graphene oxide
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ZnO nanorod-decorated graphene oxide (GO/ZnO), containing Lewis and Bronsted acid centers, was introduced as a selective, highly efficient and recoverable nanocatalyst for the pseudo three-component synthesis of diverse tetraketone or xanthenedione derivatives via condensation of aromatic aldehydes with 1,3-dicarbonyl compounds in short reaction times and good to excellent yields in H2O under refluxing and solvent-free conditions, respectively. Moreover, the GO/ZnO nanocomposite was recovered and reused at least four times without a significant decrease in its activity. Low loading of the catalyst, high to excellent yields, the elimination of any toxic heavy metals or corrosive reagents for modification of the catalyst, simple separation and purification of the products, and the reusability of the catalyst are the most significant advantages of this green protocol. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2018.
- Hasanzadeh Banakar, Sepideh,Dekamin, Mohammad G.,Yaghoubi, Amene
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p. 14246 - 14262
(2018/08/29)
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- Promiscuous enzyme-catalyzed cascade reaction: Synthesis of xanthone derivatives
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Based on the screening of biocatalysts and reaction conditions including organic solvent, water content, lipase loading, reaction temperature and time, lipase TLIM exhibited the prominent promiscuity for the Knoevenagel-Michael cascade reactions of 1, 3-diketones with aromatic aldehydes to synthesize xanthone derivatives. This procedure provides satisfactory advantages such as environmental begin, simple work-up, generality, obtaining in excellent yields (80–97%), and potential for recycling of biocatalyst.
- Fu, Yajie,Fan, Bingbing,Chen, Hongyue,Huang, He,Hu, Yi
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p. 555 - 559
(2018/07/25)
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- Synthesis and characterization of the immobilized Ni-Zn-Fe layered double hydroxide (LDH) on silica-coated magnetite as a mesoporous and magnetically reusable catalyst for the preparation of benzylidenemalononitriles and bisdimedones (tetraketones) under
-
Herein, novel magnetic Fe3O4@SiO2@Ni-Zn-Fe layered double hydroxide (LDH) intercalated with water molecules and carbonate anions as interlayer contents was prepared as a new heterogeneous and separable nanocatalyst. The me
- Gilanizadeh, Masumeh,Zeynizadeh, Behzad
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p. 8553 - 8566
(2018/06/08)
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- A reusable magnetic nickel nanoparticle based catalyst for the aqueous synthesis of diverse heterocycles and their evaluation as potential anti-bacterial agent
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A library of biologically important heterocycles, viz. pyrazolyl pyrimidine-triones, bis(heterocyclyl)methanes were successfully synthesised by the condensation of barbituric acid, pyrazolone with an aldehyde and dimedone/4-hydoxy coumarin with various su
- Bhattacharjee, Deboshikha,Sheet, Sanjoy Kumar,Khatua, Snehadrinarayan,Biswas, Koel,Joshi, Santaram,Myrboh, Bekington
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supporting information
p. 5018 - 5028
(2018/09/11)
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- Natural phosphate as an efficient and green catalyst for synthesis of tetraketone and xanthene derivatives
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Abstract: Natural phosphate was applied as an efficient and ecofriendly catalyst for the synthesis of tetraketones (2–2.5?h, 90–100?%) and xanthenes (6.5–8.5?h, 84–95?%) via Knoevenagel–Michael cascade reaction of aromatic aldehydes with 1,3-cyclic diketones in water and ethanol, respectively. This protocol provides several advantages over the traditional chemical synthesis, such as simple work-up, easy handling procedure, non-toxicity and stability of catalyst, low cost and environmental friendliness. Graphical Abstract: [Figure not available: see fulltext.]
- Fallah, Azadeh,Tajbakhsh, Mahmood,Vahedi, Hooshang,Bekhradnia, Ahmadreza
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- The cellulose aluminum oxide composite-supported imidazolium chloroaluminate ionic liquid as a novel and stable heterogeneous catalyst
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1-Methyl-3-(triethoxysilylpropyl)imidazolium chloroaluminate ionic liquid anchored on a composite of cellulose and aluminum oxide was easily synthesized and tested for its catalytic activity in one-pot Knoevenagel condensation, Michael addition, and cyclo
- Boroujeni, Kaveh Parvanak,Tahani, Parisa
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p. 1150 - 1156
(2017/08/10)
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- In water–ultrasound-promoted synthesis of tetraketones and 2-substituted-1H-benzimidazoles catalyzed by BiOCl nanoparticles
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A highly efficient, green protocol has been developed for the synthesis of various structurally diverse 2,2′-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) and 2-substituted-1H-benzimidazole derivatives. The reaction was performed in water under ultrasound irradiation, using BiOCl nanoparticles as a catalyst. The nanocatalyst was found to be reusable for seven subsequent reactions without much loss in activity. Simple methodology with short reaction times and mild reaction conditions with easy work-up procedure are the salient features of this method.
- Sapkal, Bharatkumar M.,Labhane, Prakash K.,Satam, Jitendra R.
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p. 4967 - 4979
(2017/07/22)
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- Nano Fe/NaY zeolite: An efficient and reusable solid-supported catalyst for synthesis of 1-oxo-hexahydroxanthene and tetraketone derivatives
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Nano Fe/NaY zeolite with high loading of Fe ions was successfully synthesized by the ion-exchange technique at ambient temperature. The prepared Fe/NaY was characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, Brunauer-Emmett-Teller (BET) surface area measurements, and Fourier-transform infrared (FT-IR) spectroscopy. The data analyses confirm the presence of iron oxide (up to 32.8 %) with average diameter of 30-40 nm on the surface of NaY zeolite. The catalytic activity of nano Fe/NaY zeolite was examined in the preparation of 1-oxo-hexahydroxanthene and tetraketone derivatives. The results showed its applicability as a green, reusable, and promising catalyst for organic synthesis. This protocol demonstrates several notable advantages including short reaction times, environmentally friendly conditions, no necessity for extraction or chromatographic purification steps, more convenient workup, high yields of products, and lack of use of any injurious solvents. The catalyst was recovered and reused up to four consecutive times without significant loss in catalytic activity. Graphical Abstract: [Figure not available: see fulltext.]
- Tajbakhsh, Mahmood,Heidary, Marzieh,Hosseinzadeh, Rahman
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p. 1425 - 1439
(2016/04/26)
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- Domino Knoevenagel/Michael synthesis of 2,2’-arylmethylenebis(3-hydroxy-5,5-dimethyl-2-cyclohexen-1-one) derivatives catalyzed by silica-diphenic acid and their single crystal X-ray analysis
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An efficient and eco-friendly procedure has been developed for the synthesis of various 2,2’-arylmethylenebis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) derivatives which were isolated and characterized by melting point, IR, 1H-NMR, 13/s
- Vaid, Rupali,Gupta, Monika,Kant, Rajni,Gupta, Vivek K
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p. 967 - 976
(2016/07/06)
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- Method for catalytically synthesizing xanthenedione compound open ring derivatives through hydroxyl ammonium ionic liquid
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The invention discloses a method for catalytically synthesizing xanthenedione compound open ring derivatives through hydroxyl ammonium ionic liquid, and belongs to the technical field of green synthesis of fine chemicals. According to the technical scheme
- -
-
Paragraph 0012; 0013; 0049; 0050; 0051; 0052; 0053; 0054
(2017/02/02)
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- Revisiting the three component synthesis of isoxazolo[5,4-b]pyridines, 4-aryl-3,7,7-trimethyl-isoxazolo[5,4-b]quinolin-5(6H)-ones and related heterocycles
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The one-step three-component microwave assisted synthesis between aromatic aldehydes with tetronic acid or indan-1,3-dione readily formed the Knoevenagel adducts that underwent addition of 3-methylisoxazol-5-amine 1 to form the isoxazolo[5,4-b]pyridine pr
- Lingham, Anthony R.,Hawley, John A.,Greaves, Tamar,Jackson, Neale,Antolasic, Frank,Hügel, Helmut M.
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supporting information
p. 175 - 179
(2016/12/03)
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- Introduction of taurine (2-aminoethanesulfonic acid) as a green bio-organic catalyst for the promotion of organic reactions under green conditions
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Taurine (2-aminoethanesulfonic acid), a semi-essential amino acid that exists in the human body and numerous other living creatures, is used as a green bio-organic catalyst for the promotion of the Knoevenagel reaction between aldehydes and malononitrile. In the same way, tetraketones can also be produced through a Knoevenagel reaction, followed by Michael addition. 2-Amino-3-cyano-4H-pyran derivatives are simply prepared via a three-component reaction in the presence of taurine as the catalyst. All these reactions are performed in water, a green solvent. The advantages of using of taurine as the catalyst are it is environmentally friendly, low cost, commercially available, easy to separate from the reaction mixture, and has high reusability. Use of this catalyst results in acceptable reaction times, high yields and high purities of the obtained products without utilizing any organic solvents.
- Shirini, Farhad,Daneshvar, Nader
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p. 110190 - 110205
(2016/11/30)
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- Copper (0) nanoparticles onto silica: A stable and facile catalyst for one-pot synthesis of 2,2′-arylmethylene bis (3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) via cascade Knoevenagel/Michael reaction
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Solid supported copper (0) nanoparticles were prepared by physical adsorption of copper (0) nanoparticles (synthesized through bottom-up approach) on the solid supports such as silica, HAP, cellulose and basic alumina. Studies comparing these supported ca
- GUPTA,GUPTA
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p. 849 - 854
(2016/05/19)
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- An Efficient One-Pot Two-Step Three-Component Process for the Synthesis of Trifluoromethylated Hydrochromenes
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A one-pot two-step three-component process for the synthesis of trifluoromethylated 2-hydroxy-5-oxo-3,4,5,6,7,8-hexahydro-2H-chromenes has been developed. The three-component reaction of dimedone, substituted benzaldehydes, and methyl 4,4,4-trifluorobut-2-ynoate gave the desired products in moderate to good yields. Excellent regioselectivity and diastereoselectivity were observed. Furthermore, refluxing the product chromenes with p-toluenesulfonic acid in toluene gave the corresponding dehydrated products - trifluoromethylated 5-oxo-5,6,7,8-tetrahydro-4H-chromenes.
- Yan, Xufeng,Yang, Yeqing,Han, Jing,Jiang, Guimei,Chen, Jie,Deng, Hongmei,Shao, Min,Zhang, Hui,Cao, Weiguo
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supporting information
p. 2863 - 2872
(2016/08/31)
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- Multicomponent Synthesis of Functionalized Tetrahydroacridinones: Insights into a Mechanistic Route
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A mechanistic study of three-component reactions of various aromatic amines with a number of aldehydes and 1,3-diones was achieved. The unprecedented reaction involved a nucleophilic attack of an aromatic amine on the in situ generated Michael adduct inte
- Chung, Tsai-Wen,Narhe, Bharat D.,Lin, Chun-Cheng,Sun, Chung-Ming
-
supporting information
p. 5368 - 5371
(2015/11/18)
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- Novel heterogeneous catalyst systems based on Pd(0) nanoparticles onto amine functionalized silica-cellulose substrates [Pd(0)-EDA/SCs]: Synthesis, characterization and catalytic activity toward C-C and C-S coupling reactions in water under limiting basic conditions
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Novel heterogeneous catalyst systems based on the immobilization of Pd(0) nanoparticles onto ethylene diamine functionalized silica-cellulose substrates [Pd(0)-EDA/SCs] are reported with a view to introduce new synthetic routes under base-free conditions. The base functionalized organic/inorganic hybrid provides specific basic sites for the reactions to occur under base-free or less basic conditions, and that too with excellent yields. Moreover, the basic nitrogen sites present on the substrate can effectively stabilize and enhance the activity of Pd(0) nanoparticles by preventing their agglomeration and controlling their size. All the catalysts were characterized by TGA and FTIR analysis and the most active catalyst, [Pd(0)-EDA/SC-2] was further characterized by SEM, TEM, HRTEM, EDX, CHN and XRD studies. Additionally, it is shown that the Pd(0)-EDA/SCs exhibits excellent activity under limiting basic conditions for the C-C and C-S coupling reactions employing water as the "Green solvent". Furthermore, the novel catalyst could be recovered in a facile manner from the reaction mixture and could be reused up to five times without significant loss of catalytic activity.
- Bhardwaj, Madhvi,Sahi, Seema,Mahajan, Hitesh,Paul, Satya,Clark, James. H.
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- Biotransformation of Active Methylene Compounds by Saccharomyces cerevisiae
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The biotransformation of several activated CH-acid compounds was examined using Saccharomyces cerevisiae as a biocatalyst. Alkylation-hydroxylation of 1,3-dicarbonyl compounds at the α-position was achieved. Investigation of the reaction of these compound
- Ghasemi, Sabrieh,Habibi, Zohreh,Notash, Behrouz
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p. 856 - 860
(2015/12/26)
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- Improved synthesis of 2,2-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) and 1,8-dioxo-octahydroxanthene derivatives catalyzed by electrogenerated base and sulfuric acid
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An efficient method has been developed for the synthesis of 1,8-dioxo-octahydroxanthene derivatives in two-step. In the first step, the electrogenerated base (EGB) catalyzed multicomponent transformation of dimedone and aromatic aldehydes in an undivided
- Kazemi-Rad, Reyhaneh,Azizian, Javad,Kefayati, Hassan
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p. 311 - 315
(2015/05/05)
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- Conformational analysis of 2,2'-arylmethylene bis(3-hydroxy-5,5-dimethyl-2- cyclohexene-1-one) by NMR and molecular modeling
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2,2'-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-ones) with para and ortho-R groups on the benzene ring were prepared and studied by nuclear magnetic resonance (NMR) and molecular modeling to determine their conformational exchanges. Experime
- De S. Ferreira, Marcelle,Figueroa-Villar, Jose? D.
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p. 935 - 946
(2014/06/24)
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- Zinc chloride catalyzed collective synthesis of arylmethylene bis(3-hydroxy-2-cyclohexene-1-ones) and 1,8-dioxo-octahydroxanthene/acridine derivatives
-
Catalytic amount of ZnCl2 efficiently promoted rapid synthesis of arylmethylene bis(3-hydroxy-2-cyclohexene-1-one) in water at room temperature in excellent yield. At elevated temperature, ZnCl2 also catalyzed one-pot synthesis of 1,8-dioxo-octahydroxanthene and 1,8-dioxo-decahydroacridine derivatives in good yield. In specific instances, unusual dissociation of dimedone from the arylmethylene bis(3-hydroxy-2-cyclohexene-1-one) was identified in the reaction medium. It was minimized/avoided by the addition of known excess dimedone to the reaction mixture in the one-pot synthesis of 1,8-dioxo-octahydroxanthene.
- Ganesan, Subramaniapillai Selva,Kothandapani, Jagatheeswaran,Ganesan, Asaithampi
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supporting information
p. 682 - 687
(2015/04/14)
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- "amano" lipase DF-catalyzed efficient synthesis of 2,2′-arylmethylene dicyclohexane-1,3-dione derivatives in anhydrous media
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A simple and efficient method was developed for the synthesis of 2,2′-arylmethylene dicyclohexane-1,3-dione derivatives via the Knoevenagel-Michael cascade reactions of aromatic aldehydes and 1,3-cyclic diketones catalyzed by "Amano" lipase DF, which expands the application field of enzyme catalytic promiscuity. This protocol provides several advantages over the traditional chemical synthesis, such as simple work-up procedure, high yields (up to 94%) and environmental friendliness.
- Jiang, Ling,Wang, Bo,Li, Rong-Rong,Shen, Sa,Yu, Hong-Wei,Ye, Li-Dan
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p. 1190 - 1192
(2014/08/18)
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- Rapid one pot synthesis of xanthene derivatives by an efficient and reusable nano-ZnAl2O4 - An insight into a new process
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Nano-ZnAl2O4 was synthesized by blending metal-citrate complex-acrylamide polymer using the precursor method. Powder X-ray diffraction analysis of the catalyst affirmed that the spinel oxide was phase pure. Elemental analysis was confirmed by Energy Dispersive X-ray analysis. Transmission Electron Microscopic (TEM) analysis and Scherrer's formula revealed that the particles were found to be in the order of 20 nm in size. Thermal stability of the catalyst was analyzed by thermogravimetric and differential thermal analysis (TG-DTA). Total acidity of the nano-ZnAl 2O4 evaluated by NH3-TPD was 8.8 mmol NH 3/g. Diversity in the synthesis of xanthene derivatives was investigated using nanozinc aluminate as a catalyst. Nanoform of the catalyst showed better activity than the bulk form due to its large surface area 50 m2/g. The 2,2′-arylmethylene bis (3-hydroxy-2-cyclohexene-1- one), 2,2′-arylmethylene bis (3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) and 1-Oxo-hexahydroxanthenes were synthesized rapidly using ZnAl 2O4 and the catalyst was successfully recycled without any loss of activity.
- Mandlimath, Triveni Rajashekhar,Umamahesh, Balijapalli,Sathiyanarayanan, Kulathu I.
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p. 198 - 207
(2014/06/10)
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- Efficient and rapid solvent-free synthesis of 1,8-dioxo-octahydroxanthenes and 2,2'-(Phenylmethylene)bis(3-hydroxy-5,5-dimethylcyclohex-2-en-1-ones) under microwave irradiation condition
-
Efficient and rapid solvent-free methods have been developed for synthesis of 1,8-dioxo-octahydroxanthenes by microwave irradiation of cyclohexane-1,3- diones with aromatic aldehydes in presence of either amberlyst-15 or benzoic acid as catalyst. 2,2'-(Ph
- Samanta, Swati,Das Gupta, Arpita,Mondal, Rina,Mallik, Asok Kumar
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p. 845 - 852
(2013/08/23)
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- Simple and cost effective acid catalysts for efficient synthesis of 9-aryl-1,8-dioxooctahydroxanthene
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CaCl2 (20 mol %) dispersion in DMSO or aq HBr (10 mol %) is developed as an efficient and cost effective acid catalyst for the simple one-pot synthesis of 9-aryl-1,8-dioxooctahydroxanthene derivatives. Reaction of aromatic aldehyde (1 equiv) an
- Ilangovan,Muralidharan,Sakthivel,Malayappasamy,Karuppusamy,Kaushik
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supporting information
p. 491 - 494
(2013/02/23)
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- Chemoselective synthesis of xanthenes and tetraketones in a choline chloride-based deep eutectic solvent
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A chemoselective synthesis of tetraketone and xanthene derivatives, by means of tandem Knoevenagel condensation and Michael addition in choline chloride-based deep eutectic solvents (DESs), is presented. The reaction of readily available aldehydes and act
- Azizi, Najmedin,Dezfooli, Sahar,Hashemi, Mohammad Mahmoudi
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p. 997 - 1001
(2013/11/06)
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- Improved synthesis of 2,2′-arylmethylene bis(3-hydroxy-5,5-dimethyl- 2-cyclohexene-1-one) derivatives catalyzed by urea under ultrasound
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Synthesis of 2,2′-arylmethylene bis(3-hydroxy-5,5-dimethyl-2- cyclohexene-1-one) derivatives catalyzed by urea via the condensation of aromatic aldehydes and 5,5-dimethyl-1,3-cyclohexanedione was carried out in 80-98% yields at 50 °C in aqueous media unde
- Li, Ji-Tai,Li, Yan-Wei,Song, Ya-Li,Chen, Guo-Feng
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experimental part
p. 1 - 4
(2012/04/04)
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- Nickel nanoparticles: A highly efficient catalyst for one pot synthesis of tetraketones and biscoumarins
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A novel and practically useful protocol has been designed wherein, polyvinyl pyrrolidone (PVP) stabilized nickel nanoparticles have been used as a catalyst for promoting the synthesis of 2,2'-aryl-methylene bis(3-hydroxy-5,5- dimethyl-2-cyclohexene-1-one)
- Khurana, Jitender M.,Vij, Kanika
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p. 907 - 912,6
(2020/09/09)
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- Facile microwave-promoted Knoevenagel condensation and the combination of Knoevenagel/Michael addition reaction in aqueous medium containing ionic surfactant
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A simple, efficient, environment-friendly and high yielding procedure is developed for the Knoevenagel condensation and the combination of Knoevenagel/Michael addition reaction of various 1, 3-dicarbonyls and aryl aldehydes in an aqueous surfactant medium
- Saha, Mithu,Dey, Jahar,Ismail, Kochi,Pal, Amarta K.
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experimental part
p. 554 - 558
(2012/06/04)
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- Silica chloride nano particle catalyzed synthesis of 2,2'-(arylmethylene) bis(5,5-dimethylcyclohexane-1,3-dione) derivatives
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Silica chloride nano particle (nano SiO2-Cl), has been found to be heterogeneous catalyst for fa-cile and simple condensation of dimedone with aromatic aldehydes into 2,2′-(arylmethylene)bis(5,5-dimethylcyclohexane-1, 3-dione) derivatives in dr
- Karimian, Ramin,Piri, Farideh,Karimi, Babak,Moghimic, Abolghasem
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experimental part
p. 111 - 115
(2012/02/01)
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- Catalysis by L-lysine: A green method for the condensation of aromatic aldehydes with acidic methylene compounds in water at room temperature
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The condensation of aromatic aldehydes with acidic methylene compounds such as ethyl benzoylacetate, 2,4-pentanedione and dimedone proceeded efficiently in pure water in the presence of L-lysine at room temperature. Interestingly, there are two different
- Zhang, Yan,Sun, Cuizhi,Liang, Jun,Shang, Zhicai
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experimental part
p. 2255 - 2259
(2011/10/09)
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- Reaction of aldehydes and 5,5-dimethyl-1,3-cyclohexanedione in the presence of surfactants in water
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An efficient and convenient approach to the synthesis of the two different products from aldehydes and 5,5-dimethyl-1,3-cyclohexanedione using two kinds of surfactant catalysts sodium dodecyl sulfate (SDS) and dodecanesulfonic acid (DSA) (10 mol %) is des
- Qin, Xin-Ying,Jin, Tong-Shou,Zhang, Jian-She,Li, Tong-Shuang
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experimental part
p. 1173 - 1178
(2012/03/11)
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- An efficient synthesis of 2,2′-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) and 1,8-dioxooctahydroxanthenes using ZnO and ZnO-acetyl chloride
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2,2′-Arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) 4l-s produced from reaction between dimedone with various aldehydes in acetonitrile using ZnO as a catalyst; whereas in the presence of ZnO-acetyl chloride catalysts the reaction is limite
- Maghsoodlou, Malek Taher,Habibi-Khorassani, Sayyed Mostafa,Shahkarami, Zahra,Maleki, Nariman,Rostamizadeh, Mohsen
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experimental part
p. 686 - 689
(2011/10/30)
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