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1.
Sulfonic acid groups were grafted onto three different types of synthesized magnetic nanoparticles, namely Fe3O4, Fe3O4@SiO2, and Fe3O4@MCM‐48. The sulfonic acid‐functionalized nanoparticles were evaluated as catalysts for the synthesis of 5‐aryl‐1H‐benzo[f]chromeno[2,3‐d]pyrimidine‐2,4(3H,5H)‐dione derivatives in terms of activity and recyclability. Their catalytic activities were compared with that of the homogeneous acid catalyst 1‐methylimidazolium hydrogen sulfate ([HMIm][HSO4]). The activity of Fe3O4@MCM‐48–SO3H was comparable to those of the other heter‐ogeneous and homogeneous catalysts.  相似文献   

2.
Magnetite nanoparticles coated with sulfuric acid-functionalized mesoporous MCM-48 were syn-thesized and used as a catalyst in three-component domino reactions of indoles, arylglyoxal mono-hydrates and...  相似文献   

3.
Magnetite nanoparticles coated with sulfuric acid-functionalized mesoporous MCM-48 were syn-thesized and used as a catalyst in three-component domino reactions of indoles, arylglyoxal mono-hydrates andN-arylenaminones to furnish the desired 3,3′-bisindoles by formation of two C–C and one C–N bonds in a smooth cascade with good yields under mild reaction conditions. The catalyst was recovered easily and maintained activity in successive runs.  相似文献   

4.
胡扬根  高海涛  王刚  王燕  屈永年  徐靖 《有机化学》2012,31(8):1468-1472
报道应用aza-Wittig反应,采用易得的原料,在温和的条件下,以78%~90%的产率有效的合成了新型2-氨基-呋喃并[3,2-d]嘧啶-4(3H)-酮衍生物5,其结构经IR,1H NMR,MS和元素分析确认.为进一步得到结构确认,化合物5c经X射线衍射分析证实.运用噻唑蓝(MTT)标准法对化合物5进行了体外抗肿瘤活性的测定,其中5f对肺癌细胞A459的IC50值为18.4μmol/L,显示出潜在良好的抗肿瘤活性.  相似文献   

5.
6.
An efficient method for the synthesis of benzo[b]benzofurano[2,3-e][1,6]naphthyridine-8-one derivatives has been developed via Pictet-Spengler reaction of 4-(3-aminobenzofuran-2-yl)quinoline-2-ones,which could be obtained from alkylation of 4-bromomethylquinoline-2-ones with salicylonitrile and subsequent Thorpe-Ziegier isomerization,with aromatic aldehydes under p-TsOH as catalyst in good yields.  相似文献   

7.
Fe3O4@MCM‐41@Zr‐MNPs modified with piperazine is easily prepared and characterized using Fourier transform infrared spectroscopy (FT‐IR), X‐ray powder diffraction (XRD), N2 adsorption–desorption, Transmission electron microscopy (TEM), Energy‐dispersive X‐ray (EDX), Vibrating sample magnetometry (VSM) and Thermogravimetric analysis (TGA) techniques. The characterization results showed that Zr highly dispersed in the tetrahedral environment of silica framework and piperazine is successfully attached to the surface of the nanocatalyst in connection with zirconium. The prepared nanosized reagent (10–30 nm), shows excellent catalytic activity in the synthesis of tetrahydro‐4H‐chromene and pyrano[2,3‐d]pyrimidinone derivatives. All reactions are performed under mild and completely heterogeneous reactions conditions in high yields during short reaction times. On the other hand and due to its superparamagnetic nature the catalyst can be easily separated by the application of an external magnetic field and reused for several times.  相似文献   

8.
以2-氨基-4-三氟甲基-5-甲基-噻吩-3-羧酸乙酯(1)为起始原料制得膦亚胺2.在碳酸钾的催化下,膦亚胺2与芳基异氰酸酯和伯二胺的氮杂Wittig反应制得嘧啶环上2,2’取代的双[噻吩并[2,3-d]嘧啶-4(3H)-酮]3;膦亚胺2与烷基异氰酸酯和伯二胺的氮杂Wittig反应制得嘧啶环上3,3’取代的双[噻吩并[2,3-d]嘧啶-4(3H)-酮]4.化合物3的核磁共振氢谱表明关环反应在嘧啶环的2,2’位;化合物4的核磁共振氢谱表明关环反应在嘧啶环的3,3’位.对合成反应机理的推导及目标产物核磁共振氢谱数据的分析解释了此合成反应的选择性.  相似文献   

9.
The magnetic nanoparticles supported silica sulfuric acid was used as an efficient catalyst for the synthesis of pyrimido[4,5-b]quinolines and indeno fused pyrido[2,3-d]pyrimidines in water. The desired products were obtained in excellent yields. Fe3O4@SiO2-SO3H was readily recovered using an external magnet and could be reused several times without significant loss of reactivity.  相似文献   

10.
Xiao-Hua Zeng  Min Liu  Hong-Wu He 《合成通讯》2013,43(10):1453-1460
Isothiocyanate 2, obtained from aza-Wittig reaction of iminophosphorane 1 with CS2, reacted with amine to give 2-thioxo-2,3,5,6,7,8-hexahydrobenzothieno[2,3-d]pyrimidin-4(1H)-ones 4 in the presence of sodium ethoxide. S-Alkylation of 4 produced 2-alkylthio-5,6,7,8-tetrahydrobenzothieno[2,3-d]pyrimidin-4(3H)-ones 5 in good yields.  相似文献   

11.
Chromene substructure is an important structural motif present in a variety of medicines, natural products, and materials showing biological activities. Here, a simple and convenient procedure for the synthesis of 3,4-dihydropyrano[3,2-c]chromene derivatives is described. For this purpose, Fe3O4 nanoparticles supported on β-cyclodextrin-guanidine were successfully prepared and used as catalyst. The structure of this catalyst was assigned by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, thermal gravimetric analysis, and vibrating sample magnetometer techniques. The prepared nanocomposites were used as a highly active, heterogeneous, and reusable nanocatalyst for the one-pot, three-component reaction of 4-hydroxycoumarin, aromatic aldehydes, and ethyl cyanoacetate. This method has advantages such as mild conditions, high yields, easy workup and simple purification of products, little catalyst loading, cost efficiency, and reusability of the catalyst.  相似文献   

12.
The crystal structure of the new title compound 2-ethoxy-3-n-butyl- benzofuro[2,3d]pyrimidin-4(3H)-one (C16H18N2O3, Mr = 286.32) has been prepared and determined by singlecrystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 13.7167(14), b = 13.113(1), c = 8.378(1) A, β = 98.992(2)^o, V = 1488.4(3) A^3, Z = 4, Dc = 1.278, F(000) = 608, μ = 0.089 mm^-1, MoKa radiation (2 = 0.71073), R = 0.0498, wR = 0.1238 for 2336 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals that all ring atoms in the benzo[4, 5]furo [2,3-d] pyrimi- dinone moieties are almost coplanar.  相似文献   

13.
Schemes for the synthesis of MeS-substituted pyrido[2,3-d]pyrimidin-5-one, pyrimido[4,5-d]pyrimidine, and 4-methylenepyrimido[4,5-d]pyrimidin-2-one based on 5-acetyl-6-amino-4-methylthio-2-phenylpyrimidine, which was prepared from the adduct of benzoyl isothiocyanate with acetylketeneN-benzoylaminal, were suggested.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1324–1328, July, 1995.The work was carried out with financial support from the Russian Foundation for Basic Research (Grant No. 94-03-08964).  相似文献   

14.
In this research, the main emphasis has been focused on the preparation of a novel Fe3O4-supported propane-1-sulfonic acid-grafted graphene oxide quantum dots (Fe3O4@GOQD-O-(propane-1-sulfonic acid)) that it was readily synthesized via a five-step procedure as a hitherto unreported magnetic nanocatalyst. This newly prepared Fe3O4@GOQD-O-(propane-1-sulfonic acid) nanocomposite was structurally well-established by different analytical techniques including Fourier transform infrared (FT-IR), X-ray diffraction (XRD), energy-dispersive X-ray (EDX), thermal gravimetric analysis (TGA), field emission gun-scanning electron microscope (FESEM), high-resolution transmission electron microscopy (HRTEM) and vibrating sample magnetometer (VSM) analyses. The high catalytic performance of this nanocomposite was exhibited in one-pot synthesis of dihydropyrano[2,3-c]pyrazole and 4H-chromene derivatives under mild conditions. Low reaction times, excellent yields of the products, benignity of the catalyst, easy reaction work-up and magnetic recyclability of the catalyst are the main advantages of the present protocol. Also, our research indicated that the Fe3O4@GOQD-O-(propane-1-sulfonic acid) could be reused up to five times without considerable loss of catalytic activity.  相似文献   

15.
Isatin‐SO3H coated on amino propyl modified magnetic nanoparticles (Fe3O4@APTES@isatin‐SO3H) is found to be a novel, efficient, and reusable magnetic nanocatalyst, and characterized by FT‐IR, SEM, TEM, XRD, EDX, VSM, and TGA analysis. The magnetic nanocatalyst demonstrated outstanding performance in synthesis of pyrano[2,3‐d] pyrimidines derivatives via one‐pot three‐component reaction of various aromatic aldehydes 1, malononitrile 2, and barbituric acid 3 under reflux conditions in mixture of H2O:EtOH (1:1) as solvent. Easy workup procedure, short reaction time, high yield, simple preparation and easy recovery of the catalyst, mild reaction conditions are some advantages of this work.  相似文献   

16.
In this work, a new, green and beneficial nanomagnetic catalyst was easily fabricated using sulfuric acid as an acidic group on Fe3O4 nanoparticles coated with tris (hydroxymethyl) aminomethane (THAM). The synthesized catalyst was characterized by FT-IR, TGA/DTG, XRD, TEM, EDS, VSM, and SEM analyses. Next, its catalytic activity was studied for the synthesis of dihydropyrano[2,3-c]pyrazole derivatives. This catalyst has advantages such as high catalytic activity, non-toxicity, easy separation from the reaction mixture using an external magnet and reuses for several times without significantly reducing in its catalytic activity.  相似文献   

17.
Ni-PEG (polyethylene glycol) complex supported on magnetic nanoparticle was created by grafting. The catalytic activity of Fe3O4@PEG–Ni was explored through one-pot green synthesis of 2,3-dihydroquinazolin-4(1H)-ones and used as an efficient and recoverable nanocatalyst. FT-IR, XRD, EDS, BET, TGA, VSM and SEM techniques were employed to specify the nanocatalyst. This heterogeneous nanocatalyst demonstrated acceptable recyclability and could be reused several times with no considerable loss of its catalytic activity.  相似文献   

18.
A novel chiral magnetic nanocatalyst was prepared by the surface modification of Fe3O4 magnetic nanoparticles (MNPs) with a chloropropylsilane and further by arginine to form Fe3O4@propylsilan‐arginine (Fe3O4@PS‐Arg). After the structural confirmation of Fe3O4@PS‐Arg synthesized MNPs by Fourier transform‐infrared, X‐ray diffraction, field emission‐scanning electron microscopy, transmission electron microscopy, vibrating‐sample magnetometry and thermogravimetric analyses, their catalytic activity was evaluated for one‐pot enantioselective synthesis of 3‐amino‐1‐aryl‐1H‐benzo[f]chromene‐2‐carbonitrile derivatives. The results showed that in the presence of 0.07 g Fe3O4@PS‐Arg nanocatalyst and ethanol as solvent, the best reaction yield (96%) was obtained in the least time (5 min). Easy operation, reusability and stability, short reaction time, high reaction yields and good enantioselectivity are the major advantages of the newly synthesized nanocatalyst. Also, this study provides a novel strategy for further research and investigation on the synthesis of new reusable enantioselective catalysts and chiral compounds.  相似文献   

19.
A facile one-pot synthesis of new 3-arylthieno[2,3-d]pyrimidine-2,4(1H,3H)-diones via base-catalyzed cyclocondensation of ethyl 2-amino-4,5-dimethylthiophene-3-carboxylate with aryi isocyanates is described.  相似文献   

20.
The zwitterionic intermediates generated from dialkyl azodicarboxylates and triphenylphosphine displayed excellent reactivity toward 3-formylchromones to afford chromeno[2,3-c]pyrazolines and chromeno[2,3-e]tetrazepines.  相似文献   

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