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1.
A mechanistically unique and serendipitously discovered reaction providing a variety of pyridine–urea hybrids via the thiophenol‐initiated uracil ring opening and pyridine ring‐forming process was reported. The identification process of the hybrids and the pathway through which they were formed were also briefly described. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:362–368, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20560 相似文献
2.
Synthesis of novel isoxazole-benzoquinone hybrids via 1,3-dipolar cycloaddition reaction as key step
P. Ravi Kumar Manoranjan BeheraK. Raghavulu A. Jaya ShreeSatyanarayana Yennam 《Tetrahedron letters》2012,53(32):4108-4113
An efficient method for the preparation of novel 2-(5-arylisoxazol-3-yl)cyclohexa-2,5-diene-1,4-dione hybrids via 1,3-dipolar cycloaddition followed by an oxidation reaction using ceric ammonium nitrate (CAN) has been described. Using this method, various aryl as well as alkyl substituted isoxazole-benzoquinone hybrids were synthesized in high yields. 相似文献
3.
Eli Ruckenstein Wusheng Yin 《Journal of polymer science. Part A, Polymer chemistry》2000,38(9):1443-1449
SiO2–poly(amidoamine) (PAMAM) dendrimer hybrids were synthesized via (1) a Michael addition reaction between the dendrimer and 3‐(trimethoxysilyl) propyl acrylate, (2) the dissolution of the formed compound in methanol, and (3) the mixing of the latter solution with a methanol solution of partly hydrolyzed tetraethylorthosilicate (TEOS) and its casting on a glass substrate. 1H NMR indicated that in the first step, 77% of the secondary amines were converted into tertiary amines when the fourth‐generation dendrimer was employed and 46% were converted when the second‐generation dendrimer was used. The final SiO2–PAMAM dendrimer hybrids were obtained via the hydrolysis and condensation of the compound obtained via the Michael addition and the methanol solution of partly hydrolyzed TEOS. The compartmentalized structure of the hybrids due to the compartments of the dendrimers could be controlled by changing the dendrimer and the amount of TEOS. Scanning electron microscopy and transmission electron microscopy micrographs provided information about the structure of the hybrids. Like the PAMAM dendrimer, the SiO2–PAMAM dendrimer hybrids exhibited a high metal ion complexing capacity because of the presence of the compartments of the dendrimer; they can be, however, much more easily handled, and, as demonstrated by thermogravimetric experiments, have much higher thermal resistance. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1443–1449, 2000 相似文献
4.
Guguloth V. Thirukovela N. S. Paidakula S. Vadde R. 《Russian Journal of General Chemistry》2020,90(3):470-475
Russian Journal of General Chemistry - Some novel isoxazole-phenothiazine hybrids have been synthesized regioselectively in high yields via Cu(I) catalyzed one-pot reaction of... 相似文献
5.
[reaction: see text] A series of new adamantyl-oligoethyleneglycol-fullerene hybrids was prepared via Bingel-Hirsch functionalization of the C60 fullerene with various adamantyl-oligoethyleneglycol malonates. As NMDA-targeted antioxidants, these compounds may have the potential to be developed as therapeutic agents for the treatment of neurological disorders. 相似文献
6.
Olsen CA Jørgensen MR Hansen SH Witt M Jaroszewski JW Franzyk H 《Organic letters》2005,7(9):1703-1706
[reaction: see text] A mild resin-immobilization strategy employing a readily prepared trityl bromide resin for anchoring building blocks via a phenol group has been developed. With N(alpha)-Fmoc-Tyr-OPfp as a starter building block, it was possible to prepare asymmetrically substituted hybrids of spider- and wasp-type polyamine toxins using solid-phase peptide synthesis conditions. 相似文献
7.
Ashok Kumar B. Shanmukha Kumar Jagarlapudib V. 《Russian Journal of General Chemistry》2019,89(12):2512-2515
Russian Journal of General Chemistry - Regioselective synthesis of some novel isoxazole-benzimidazole hybrids in high yields via Cu(I)-catalyzed tandem one-pot reaction of aromatic aldehydes with... 相似文献
8.
Thaler T Guo LN Steib AK Raducan M Karaghiosoff K Mayer P Knochel P 《Organic letters》2011,13(12):3182-3185
Sulfoxide-alkene hybrids are introduced as a new class of chiral heterodentate ligands for the Hayashi-Miyaura reaction. The synthesis of these ligands was achieved without the use of protecting groups. A chiral resolution was performed via simple column-chromatographic separation of the diastereomeric ligands. Both diastereomers proved to be excellent ligands in Rh-catalyzed 1,4-addition reactions, furnishing chiral products with high enantioselectivities and, remarkably, opposite stereoconfigurations. 相似文献
9.
Ahmet Nebioglu 《European Polymer Journal》2007,43(8):3325-3336
Polyester acrylate inorganic/organic hybrids were prepared using a sol-gel precursor, coupling agent, and reactive diluent. The hybrids were cured via a UV-free radical initiator. Design of experiments (DOE) was utilized to investigate reaction kinetics and complex variable interactions. The effects of the silicate groups on the free radical photo-curing reaction kinetics were investigated utilizing a time-resolved Fourier transform infrared (FT-IR) spectroscopy and a differential scanning calorimeter equipped with a photocalorimetric accessory (photo-DSC). Microgel and inorganic network formation during the UV-initiated free radical crosslinking reactions was suggested to describe the complex gel-point behavior. It was proposed that the formation of the inorganic silicate groups retarded the organic crosslinking reactions. The UV-cured inorganic/organic hybrid films exhibited more homogeneous film morphology compared to the organic counterparts. In the hybrid films, a core-shell like inorganic/organic particle morphology was observed. The UV-crosslinked organic phase forms the core, whereas, the inorganic silicate forms the surrounding shell. 相似文献
10.
Research on Chemical Intermediates - A series of symmetrical bis(urea-1,2,3-triazole) hybrids (5a–5f, 6a–6f) were synthesized via Cu(I)-catalyzed click reaction followed by... 相似文献
11.
Neumann D Fisher M Tran L Matisons JG 《Journal of the American Chemical Society》2002,124(47):13998-13999
Organic-inorganic hybrids are an important class of new materials that offer improved thermal and mechanical properties over normal polymers. They may be produced by either the sol-gel route or through the use of inorganic compounds possessing reactive functional groups. Polyhedral oligosilsesquioxanes (POSS) are completely defined molecules of nanoscale dimensions that may be functionalized with reactive groups suitable for the synthesis of new organic-inorganic hybrids. Here we report the synthesis and characterization of a novel POSS possessing eight isocyanate groups via the hydrosilylation of octakis(hydridodimethylsiloxy)octasilsesquioxane (Q8M8H) and m-isopropenyl-alpha,alpha'-dimethylbenzyl isocyanate (m-TMI). The suitability of this new macromer to the synthesis of a organic-hybrids has been explored by forming a new type of highly cross-linked polyurethane elastomer via reaction of the macromer with poly(ethylene glycol) using dibutyltin dilaurate catalyst. 相似文献
12.
Polyurethane (PU)/silica nanocomposites (PSNs) were synthesized using the grafting from technique by incorporation of inorganic nano-sized silica building blocks into a polyurethane matrix. Structurally well-dispersed and stable hybrids were obtained via a two-step functionalized reaction. Firstly, 3-aminopropyltriethoxysilane (APTS) was employed to encapsulate silica as the core surface. Secondly, the PU shell was tethered to the silica core surface via surface functionalization. In order to obtain complete encapsulation of silica with APTS, different ratios of APTS to silica were investigated. The mechanism of the incorporation process was also revealed. PSNs hybrids were characterized by attenuated total reflectance and Fourier transform infrared spectroscopies, differential scanning calorimetry, thermogravimetric analysis, and transmission electron microscopy. 相似文献
13.
14.
Xin Wang Yuan Hu Lei Song Weiyi Xing Hongdian Lu 《Journal of Polymer Science.Polymer Physics》2010,48(6):693-705
Epoxy resin (EP)/polyhedral oligomeric silsesquioxane (POSS) hybrids were prepared based on octavinyl polyhedral oligomeric silsesquioxane (OVPOSS) and phosphorus‐containing epoxy resin (PCEP). The PCEP was synthesized via the reaction between bisphenol A epoxy resin (DGEBA) and 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO). The structure and morphology of PCEP/OVPOSS hybrids were characterized by Fourier transform infrared spectroscopy and transmission electron microscopy. Differential scanning calorimetry revealed that the PCEP/OVPOSS hybrids possessed higher glass transition temperatures than that of PCEP. The thermal stability of the PCEP/OVPOSS hybrids was studied using thermogravimetric analysis (TGA). The TGA results illustrated the synergistic effect of phosphorus–silicon of flame retardancy: phosphorus promotes the char formation, and silicon protects the char from thermal degradation. The thermal degradation mechanism of the PCEP/OVPOSS hybrids was investigated by real time Fourier transform infrared spectra and pyrolysis/gas chromatogram/mass spectrometry (Py‐GC/MS) analysis. It was found that OVPOSS migrated to the surface of the matrix and then sublimed from the surface in nitrogen; whereas, the vinyl groups of OVPOSS were oxidated to form a radical trap which could react with pyrolysis radicals derived from PCEP to form the branched and crosslinked structure in air. The combustion behaviors of the hybrids were evaluated by micro combustion calorimetry. The addition of OVPOSS obviously decreased the value of peak heat release rate and total heat release of the hybrids. Moreover, scanning electron microscopy (SEM) and X‐ray photoelectron spectroscopy were used to explore the char residues of the PCEP and the hybrids. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 693–705, 2010 相似文献
15.
以氯化铜(CuCl2)为研究对象,通过变换有机元制备了3种结构相似的层状类钙钛矿结构的有机-无机杂合物.用扫描电子显微镜(SEM)、X射线衍射分析(XRD)和FT-IR分别对这3种杂合物的无机元、有机元和晶体结构以及各组分问的相互作用进行分析.实验结果表明,当有机元为链状烷基胺时,层状结构非常明显,而当有机元为带刚性苯... 相似文献
16.
Mohamed A. Mohamed Teleb Ahmed E. M. Mekky Sherif M. H. Sanad 《Journal of heterocyclic chemistry》2021,58(9):1825-1835
In this study, ethyl 3-aminothieno[2,3-b]pyridine-2-carboxylate was taken as a versatile precursor for the one-pot three-component synthesis of related fused pyrimidine hybrids. The tandem protocol involved the reaction of 3-aminothieno[2,3-b]pyridine, dimethylformamide-dimethylacetal, and amines. The reaction afforded a new series of the target pyrimidine hybrids, linked to different arene units, in good to excellent yields. The prior reaction was evaluated in different solvents under traditional heating or microwave irradiation. Moreover, the influence of reaction temperature was also examined. The optimal conditions were obtained under microwave irradiation in dioxane at 110°C for 40 to 60 min. Additionally, by repeating the previous tandem reaction using the appropriate amines at reaction times of 20 to 60 min, a new series of pyrimidine hybrids linked to alkyl, arylthiazole, and benzo[d]thiazole units has been prepared in good to excellent yields. Furthermore, the utility of bis(amines) was examined to conduct the synthesis of new bis(pyrimidine) hybrids linked to aliphatic cores, in excellent yields, using the same protocol at 30 min reaction time. 相似文献
17.
A core-corona polymer hybrid with a raspberry-like structure was synthesized via the heterocoagulated pyridium reaction between the pyridyl group of poly(ethylene glycol dimethacrylate-co-methacrylic acid)@poly(ethylene glycol dimethacrylate-co- vinylpyridine) (poly(EGDMA-co-MAA)@poly(EGDMA-co-VPy)) core-shell small microspheres and the chloromethyl group of poly(divinylbenzene-co-chloromethyl styrene) (poly(DVB-co-CMSt)) microspheres, in which poly(EGDMA-co-MAA)@poly(EGDMA-co-VPy) acted as the corona and poly(DVB-co-CMSt) behaved as the core. The control coverage of the corona particles on the surfaces of core microspheres for the polymer hybrid was studied in detail through the adjustment of the mass ratio between the core and corona particles. The effects of the pH and solvents on the stability of the raspberry-like core-corona hybrids were investigated. The water static angle on the surface of polycarbonate (PC) film was studied using a contact angle system. The polymer particles and the resultant heterocoagulated raspberry-like hybrids were characterized with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The nature of the heterocoagulation between the core microspheres and corona particles was identified as the covalent pyridium reaction with Fourier transform infrared (FT-IR) spectroscopy. 相似文献
18.
Jianhu Yang Lihua Qiu Baoqiang Liu Yingjing Peng Feng Yan Songmin Shang 《Journal of polymer science. Part A, Polymer chemistry》2011,49(21):4531-4538
Herein, we present a facile approach for the synthesis of polymeric ionic liquids (PILs) microspheres for metal scavenging and catalysis. Crosslinked poly(1‐butyl‐3‐vinylimidazolium bromide) microspheres with the diameter of about 200 nm were synthesized via miniemulsion polymerization, in which 1,4‐di(vinylimidazolium) butane bisbromide was added as the crosslinker. Anion exchange of PIL microspheres with Pt precursor and followed by the reduction of Pt ions produced PIL microsphere supported Pt nanoparticle hybrids. The synthesized Pt nanoparticles with a diameter of about 2 nm are uniformly dispersed and strongly bound to the surface of PIL microspheres. The catalytic performances of PIL/Pt nanoparticle hybrids were evaluated for both the electrocatalytic oxidation of methanol and oxidation of benzyl alcohol. The PIL/Pt nanoparticle hybrids show better electrocatalytic activity towards the electrooxidation of methanol than pure Pt nanoparticles. Furthermore, they are effective and easily reusable catalysts for the selective oxidation of benzyl alcohol in aqueous reaction media, demonstrating that the synthesized PIL microspheres are suitable scaffolds for heterogeneous catalysts Pt. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
19.
Zhu Y Xiao Z Wang L Yin P Hao J Wei Y Wang Y 《Dalton transactions (Cambridge, England : 2003)》2011,40(28):7304-7309
Three novel rigid-rod conjugated organic-POM hybrids (1, 2 and 3) containing pendant amino terminus, with different rod lengths and different substituents on the rod, have been respectively synthesized via one-pot reaction of hexamolybdate and the corresponding aromatic diamine (for 1 and 2) and reaction of octamolybdate and the corresponding aromatic diamine dihydrochloride (for 3) with N,N'-dicyclohexylcarbodiimide (DCC) as a dehydrating agent. These complexes have been characterized by UV/Vis, IR, (1)H NMR, ESI and single-crystal X-ray diffraction techniques. The influences of the rod length and substituents on the properties of these compounds have been systematically investigated, which provide necessary information for further preparations of complicated hybrid materials via reactions with pendant amino groups. 相似文献
20.
《Arabian Journal of Chemistry》2022,15(2):103560
A robust design and synthesis of novel phthalazinone based indole-pyran hybrids as cytotoxic agents is described. A relatively safer ionic liquid medium ([BMIM]BF4) was utilized to mediate a one-pot, four-component reaction to access the novel hybrids in short reaction time and good yields. The cytotoxic potential of the hybrids was investigated against selected cancer cell lines. The hybrids 5h and 5b displayed potent activity with IC50 values in the range of 5.8–9.6 μM. The insilico docking demonstrated a pronounced affinity of hybrids 5h and 5b towards the human tankyrase-1 enzyme exhibiting binding energies values of ?11.2 and ?10.2 kcal/mole, respectively. Additional ADME and drug likeliness analyses revealed the potential of the active hybrids to be taken forward for advanced studies. 相似文献