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1.
An efficient, environmentally friendly procedure for the synthesis of amidoalkyl naphthols through the one‐pot, three‐component reaction of β‐naphthol, aryl aldehydes, and acetamide in the presence of a carbon‐based solid acid under thermal solvent‐free conditions is described. The beneficial fea-tures of this new synthetic approach include short reaction time, high yields, clean reaction profiles, and a simple work‐up procedure. Furthermore, the catalyst can be readily recycled and reused four times without obvious significant loss of activity. The structure of the catalyst was confirmed by Fourier transform infrared spectroscopy, N2 adsorption/desorption analysis, and X‐ray diffraction.  相似文献   

2.
In the present study, a novel magnetically retrievable catalytic system involving indium nanoparticles on magnetic carbon nanotube (Fe3O4-CNT-In) was synthesized and characterized using various techniques, such as Fourier transform-infrared, thermogravimetric analysis, energy-dispersive X-ray analysis, vibrating-sample magnetometry1, X-ray diffraction, field emission-scanning electron microscopy and inductively coupled plasma-optical emission spectrometry. The catalytic activity of the synthesized nanocatalyst was evaluated in green synthesis of isochromeno[4,3-c]pyrazole-5(1H)-one derivatives from the reaction of ninhydrin and arylhydrazones under solvent-free conditions. The catalyst was magnetically separated from the reaction mixture using an external magnet and recovered for five cycles without an appreciable decrease in its catalytic efficiency. Performing the reactions in environmentally friendly and affordable conditions, the low catalyst percentage, high yield of products, short reaction times, large substrate scope and easy work-up are the merits of this protocol. Furthermore, four of the synthesized isochromeno[4,3-c]pyrazole-5(1H)-one derivatives are also new.  相似文献   

3.
Tungstate sulfuric acid (TSA) was prepared, characterized, and applied for direct synthesis of novel and known benzimidazoles through a condensation reaction of o-phenylenediamines with orthoesters under solvent-free conditions. TSA was characterized by powdered X-ray diffraction (XRD), X-ray fluorescence (XRF), and FTIR spectroscopy. This novel and eco-friendly method is very cheap and has many advantages such as excellent yields, recyclable and eco-friendly catalyst, and simple work-up procedure.  相似文献   

4.
1-Phenyl-3-methyl-4-touloyl-5-pyrazolone (ligand) was synthesized and used to prepare an oxovanadium(IV) complex. The complex was characterized by single-crystal X-ray analysis and various spectroscopic techniques. The single-crystal X-ray analysis of the complex shows that the ligands are coordinated in a syn configuration to each other and create a distorted octahedral environment around the metal ion. A heterogeneous catalyst comprising an oxovanadium(IV) complex and hydrous zirconia was synthesized, characterized by various physicochemical techniques, and successfully used for the solvent-free oxidation of styrene. The influence of the reaction parameters (percent loading, molar ratio of the substrate to H(2)O(2), amount of catalyst, and reaction time) was studied. The catalyst was reused three times without any significant loss in the catalytic activity.  相似文献   

5.
采用新型无溶剂反应和回流的方法制得锰钾矿型氧化镁(K-OMS-2),同时采用常规方法制得氧化镁,并测试不同催化剂对工业排放气中有机挥发性物质(VOCs)中的模型化合物––乙酸乙酯和乙酸丁酯的催化氧性能.采用N2吸附-脱附、X射线衍射、扫描电镜、程序升温还原和X射线光电子能谱等技术对催化剂进行了表征.所有氧化镁样品均表现出很高的催化乙酸乙酯和乙酸丁酯氧化生成CO2的活性,且制备方法对催化剂性能起着重要作用.新型无溶剂法制得的K-OMS-2纳米棒样品比常规的回流法制得样品表现出更好的催化性能,含锰钾矿型氧化镁的样品比常规方法制得样品表现出更高的活性.性能最好的催化剂也表现出较高的稳定性,在213和202 oC条件下,可分别使90%的乙酸乙酯和乙酸丁酯转化为CO2.催化剂性能的显著差异清楚地表明,对于所选VOCs氧化反应,采用新型无溶剂法制得的K-OMS-2纳米棒样品比常规法制备的氧化镁混合物更好,这可能与样品结构中含有更高的Mn平均氧化态有关.本文表明了催化剂性能与其表面化学性质间存在显著的关联,显示了K-OMS-2内在性质决定了其高的催化性能.  相似文献   

6.
In this study, a new and stable Ce(IV) immobilized on halloysite nanotube–functionalized dendrimer was designed, synthesized, and characterized using Fourier-transform infrared, elemental analysis, thermogravimetric analysis, field emission scanning electron microscopy, scanning electron microscopy–energy dispersive X-ray spectroscopy, transmission electron microscopy, dynamic light scattering, Brunauer–Emmett–Teller, and inductively coupled plasma optical emission spectroscopy techniques. This catalyst was efficiently used for the one-pot, single-step multicomponent synthesis of pyrido[3,2-c]coumarins from 4-aminocoumarin, aldehydes, and aryl ketones. The efficiency and selectivity of this catalytic system were also evaluated for the synthesis of pyrido[3,2-c]coumarins from terminal/internal alkynes instead of aryl ketones. In this respect, the regioselectivity of the products was successfully assigned by X-ray crystallographic analysis. All these reactions were best performed under solvent-free conditions in the presence of only 0.28 mol% of the catalyst, and such a one-pot multicomponent synthesis of pyrido[3,2-c]coumarins is reported for the first time. It is also worth noting that single-step and short reaction path for the synthesis of a variety of pyrido[3,2-c]coumarins along with excellent reusability of this dendritic catalyst makes this method economically and environmentally attractive.  相似文献   

7.
A catalytic system comprising mesoporous silica functionalized with Cu(II)-DiAmSar was synthesized. This was demonstrated as an efficient heterogeneous catalyst for the synthesis of biologically useful pyridopyrazine and quinoxaline heterocycles under solvent-free conditions. X-ray diffraction, transmission electron microscopy, N2 adsorption-desorption, Fourtier transformation infrared spectroscopy, and thermogravimetric analysis were used to characterize the catalyst and investigate the texture of SBA-15 during the grafting process.  相似文献   

8.
NaY zeolite functionalized by sulfamic acid/Cu(OAc)_2[NaY/SA/Cu(Ⅱ)] was synthesized and used as a new,efficient and recyclable catalyst for preparation of formamides. This novel organic-inorganic hybrid catalyst was characterized by several techniques such as FT-IR, XRD, SEM, EDX and TG analysis.Chemoselectivity, easy procedure, excellent yields, very short reaction times, solvent-free and mild reaction conditions are some benefits of this new protocol.  相似文献   

9.
Summary. A simple and efficient procedure was developed for the synthesis of S-alkyl (aryl) thiocarbamates under solvent-free conditions without the use of a catalyst. The significant features of this protocol are (a) operational simplicity, (b) mild reaction conditions, (c) short reaction times, (d) solvent-free conditions, and (e) high product yields.  相似文献   

10.
Novel and powerful fibroin-functionalized magnetic carbon nanotube–supported silver nanoparticles (CNT–Fe3O4–fibroin–Ag) were successfully synthesized as a nontoxic and inexpensive biocatalyst. The structure of the organic–inorganic hybrid bionanocomposite was characterized by various techniques such as Fourier transform infrared spectroscopy, thermogravimetric analysis, energy-dispersive X-ray, field emission-scanning electron microscopy, transmission electron microscopy, X-ray diffraction, vibrating sample magnetometry, atomic absorption spectroscopy, and inductively coupled plasma-optical emission spectrometry. Then, the catalytic activity of synthesized bionanocomposite was evaluated in the three-component A3 coupling reaction under solvent-free conditions with good to excellent yields. Several propargylamine derivatives were synthesized by the reaction of different aldehydes with amines and phenylacetylene. Biodegradability, biocompatibility, availability, easy synthesis, high stability, high-throughput, cost-effectiveness, and efficient magnetic separation are some advantages of this catalyst that make it economically justified and sustainable. Moreover, the catalyst can be recycled for several runs without appreciable loss in its catalytic activity.  相似文献   

11.
We report synthesis of silica nanospheres containing ferrocene-tagged imidazolium acetate (SiO2@Im-Fc[OAc]) as efficient heterogeneous nanocatalyst for synthesis of naphthopyran derivatives under solvent-free conditions, based on modification of nano SiO2 by ionic liquid with ferrocene tags and subsequent anion metathesis reaction. The synthesized novel nanocatalyst (SiO2@Im-Fc[OAc]) was systematically characterized using Fourier-transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction analysis, and field-emission scanning electron microscopy. The catalytic activity of (SiO2@Im-Fc[OAc]) was tested in one-pot three-component reaction of aromatic aldehydes, malononitrile, and 2-naphthol for facile synthesis of naphthopyran derivatives. To achieve high catalytic efficacy, the effects of various reaction parameters such as temperature, amount of catalyst, type of solvent, etc. were investigated. Furthermore, recovery and reuse of the nanocatalyst several times was demonstrated without appreciable loss in catalytic activity. The presented protocol offers several advantages, including green and ecofriendly nature, operational simplicity, higher yield, and easy recovery and reuse of the nanostructured catalyst. The workup of these very clean reactions involves only recrystallization of the product from ethanol and recovery of the catalyst by filtration.  相似文献   

12.
Nickel hexacyanoferrate nanoparticles were synthesized and characterized using elemental analysis, thermal analysis, infrared spectroscopy, and X-ray diffraction. A FE-SEM image of the nickel hexacyanoferrate showed that it consists of nearly spherical particles with sizes ranging from 30 to 70 nm. The synthesized material was found to be a heterogeneous catalyst useful for the solvent-free oxidation of benzyl alcohol with H2O2 as an oxidant. A 36% conversion of benzyl alcohol to benzaldehyde was achieved under optimized reaction conditions using specific parameters such as the amount of catalyst, the temperature, the benzyl alcohol to H2O2 molar ratio, and the reaction time.  相似文献   

13.
An facile and efficient protocol for the synthesis of 13-aryl-indeno[1,2-b]naphtha[1,2-e]pyran- 12(13H)- ones has been developed that proceeds via the one-pot three-component sequential reaction of an aromatic aldehyde with β-naphthol and 2H-indene-1,3-dione under solvent-free conditions in the presence of a poly(4-vinylpyridinium)hydrogen sulfate (P(4-VPH)HSO4) catalyst. The catalyst can be reused several times, making this procedure facile, practical, and sustainable. The simple experimental procedure, solvent-free reaction conditions, use of an inexpensive catalyst, short react time, and excellent yields are some of the major advantages of this methodology.  相似文献   

14.
A simple one-pot synthesis has been developed for the synthesis of amidoalkyl naphthols using an efficient and recyclable nanocrystalline PbS catalyst under solvent-free condition. Using this nanocrystalline solid catalyst, the reactions could be carried out under mild reaction conditions with very good yield (85–95 %). This catalyst could be recycled very easily, which makes this methodology environmentally benign. The biologically active drug-like molecule 1-aminomethyl-2-naphthol derivatives can be easily obtained from 1-amidomethyl-2-naphthol by amide hydrolysis reaction in the presence of PbS nanoparticles. Characterization of the catalyst was performed by X-ray diffraction, transmission electron microscopy, and adsorption/desorption analysis (BET).  相似文献   

15.
The present article describes an efficient one-pot method for the preparation of spiro[diindeno[1,2-b:2′,1′-e]pyridine-11,3′-indoline]-trione derivatives from a three-component condensation reaction of 1,3-indandione, aromatic amines and isatins in the presence of a zinc terephthalate metal-organic framework Zn (BDC) MOF as the catalyst under solvent-free conditions. High yields, short reaction times, simple workup and environmentally benign procedure are advantages of this protocol. The Zn (BDC) MOF catalyst can be recovered and reused several times without loss of activity. The catalyst was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infra red, X-ray powder diffraction and thermal gravimetric analysis.  相似文献   

16.
A sulfonic acid functionalized ionic liquid was designed, synthesized and successfully used as a Brønsted acid catalyst for the one-pot synthesis of α-aminophosphonates containing benzothiazole at room temperature under solvent-free conditions in excellent yields. The advantages of this method are the reusability of the catalyst, high conversion, short reaction time, and simple experimental procedure. A computer modeling and docking simulation of ligand bond complexes of cyclin-dependent kinase 2 are presented. The results indicate that diethyl ((4-(dimethylamino) phenyl) ((6-nitrobenzo[d]thiazol-2-yl) amino)methyl)phosphonate was found to be the best selective inhibitor of cyclin-dependent kinase 2.  相似文献   

17.
A new, convenient, and high yielding procedure for the synthesis of triazolo[1,2-a]indazole-triones by the condensation reaction between dimedone, aryl aldehydes, and ueazoles in the presence of a catalytic amount of sulfonated polyethylene glycol (PEG-SO3H) as a highly stable and reusable eco-friendly degradable polymeric catalyst is described under solvent-free conditions. This procedure has also been applied successfully for the synthesis of novel spiro triazolo[1,2-a]indazole-tetraones.  相似文献   

18.
A new magnetically separable catalyst consisting of ferric hydrogen sulfate supported on silica-coated nickel ferrite nanoparticles was prepared. The synthesized catalyst was characterized using vibrating sample magnetometry, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and Fourier transform infrared spectroscopy. This new magnetic catalyst was shown to be an efficient heterogeneous catalyst for the synthesis of 1,8-dioxodecahydroacridines under solvent-free conditions. The catalyst is readily recovered by simple magnetic decantation and can be recycled several times with no significant loss of catalytic activity.  相似文献   

19.
Clay-supported heteropolyacid catalyst has been prepared and investigated as a novel heterogeneous, reusable and efficient catalyst for the one-pot synthesis of β-phosphonomalononitriles under ultrasound irradiation at room temperature. Compared with traditional methods, the present method is solvent-free, works under milder and cleaner conditions, furnishes products with higher purity and yields, needs shorter reaction time, easier work-up procedure, and generates less waste. No column purification is required and the products can be purified by simple crystallization. The catalyst can be easily recovered and reused several times without significant loss of its catalytic activity. The catalyst was characterized by scanning electron microscopy, X-ray powder diffraction, and thermal gravimetric, surface area, and elemental analyses.  相似文献   

20.
A new magnetically separable catalyst consisting of ferric hydrogen sulfate supported on silica-coated nickel ferrite nanoparticles was prepared.The synthesized catalyst was characterized using vibrating sample magnetometry,X-ray diffraction,transmission electron microscopy,scanning electron microscopy,and Fourier transform infrared spectroscopy.This new magnetic catalyst was shown to be an efficient heterogeneous catalyst for the synthesis of 1,8- dioxodecahydroacridines under solvent-free conditions.The catalyst is readily recovered by simple magnetic decantation and can be recycled several times with no significant loss of catalytic activity.  相似文献   

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