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1.
《应用有机金属化学》2017,31(12)
A novel hydrophobic copper complex supported on γ‐Fe2O3 is synthesized and characterized by different methods such as FT‐IR, XRD, TEM, SEM, TGA, VSM, ICP and CHN analysis. It was used as a magnetically recyclable heterogeneous catalyst for the efficient synthesis of α‐aminophosphonates via a one‐pot three‐component reaction under solvent‐free conditions. The present catalytic system worked extremely well for the synthesis of α‐aminophosphonates even up to five subsequent trails without significant loss of its catalytic activity or copper leaching. The TEM image and FT‐IR spectrum of the catalyst after five times recovery showed that the structure of the catalyst was stable under the reaction conditions with no change being observed. The strong magnetic properties of the reused catalyst were revealed by complete and easy attraction using an external magnet and also by VSM curve. This work represents the first and unique example of a hydrophobic copper complex for catalysis in water generating reactions. 相似文献
2.
Some task‐specific ionic liquids N,N,N′,N′‐tetramethyl‐N,N′‐dipropanesulfonic acid ethylene‐diammonium hydrogen sulfate, N,N,N′,N′‐tetramethyl‐N,N′‐dipropanesulfonic acid‐1,3‐propanediammonium hydrogen sulfate, N,N,N′,N′‐ tetramethyl‐N,N′‐ dipropanesulfonic acid‐1,6‐hexanediammonium hydrogen sulfate were prepared. These ionic liquids could be used as efficient and recyclable catalysts for the synthesis of α‐aminophosphonates at room temperature via an one‐pot three‐component reaction under organic solvent‐free conditions with good yields of 83–96%. The postprocessing was simple, and the catalysts could be reused at least six times without noticeably decreasing the catalytic activity. The novel clean procedure offers the advantages including short reaction time, good yields, operational simplicity, and environmentally benign. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 22:1–5, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20647 相似文献
3.
Two types of reactions, namely the Pudovik reaction of benzaldehyde and acetophenone with diethyl phosphite as well as the substitution of the α‐hydroxyphosphonates so‐formed by primary amines to afford α‐aminophosphonates, were evaluated by quantum chemical calculations at the B3LYP/6‐31G(d,p) level. An unexpected neighboring group effect was found to enhance the substitution. A series of new α‐aminophosphonates was synthesized by the microwave‐assisted substitution of α‐hydroxyphosphonates by alkylamines. 相似文献
4.
Mohan Gundluru Santhisudha Sarva Madhu Kumar Reddy Kandula Vasudeva Reddy Netala Vijaya Tartte Suresh Reddy Cirandur 《Heteroatom Chemistry》2016,27(5):269-278
A series of new α‐aminophosphonates containing 1,3,4‐thiadiazole moiety (4a–l) were synthesized via a simple, efficient, and one‐pot three‐component Kabachnik–Fields reaction of 2‐amino‐5‐ethyl‐1,3,4‐thiadiazole with various aryl/heteroaryl aldehydes and diethylphosphite under solvent‐free microwave irradiation conditions using phosphosulfonic acid, as a reusable and heterogeneous solid acid catalyst. All the title compounds were screened for radical scavenging activity by DPPH and H2O2 methods, and antimicrobial activity against bacteria (Gram‐positive and Gram‐negative) and fungi using the disc diffusion technique. They exhibited potent in vitro antioxidant and moderate antimicrobial activity. 相似文献
5.
A series of novel α‐aminophosphonates were synthesized from diterpenic dehydroabietylamine, and their structures were characterized by IR, 1H NMR, and 31P NMR spectroscopy. Their antitumor activities against SMMC7721 liver cancer cells were evaluated by the MTT method. Compounds 4 and 6 exhibited higher activities even at very low concentrations, and the inhibition ratios reached 75% and 79% at 0.1 µM, respectively. The inhibition ratio of compound 9 reached 99% after 72‐h incubation. α‐Aminophosphonates with a fluorine atom and a nitro group fused to the benzene ring exhibited higher activities. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:512–516, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20471 相似文献
6.
Mtys Milen Pter brnyi‐Balogh Rka Kangyal Andrs Dancs Dvid Frigyes Gyrgy Keglevich 《Heteroatom Chemistry》2014,25(4):245-255
Two series of bis(α‐aminophosphonates) were synthesized by one‐pot three‐component reactions using 4‐phenylenediamine, an aldehyde (2 equiv) and a phosphite (2 equiv), or terephtalaldehyde, an amine (2 equiv), and a phosphite (2 equiv) together with propylphosphonic anhydride (T3P®) in both series as a coupling reagent. The bis(α‐aminophosphonates) were obtained in moderate to excellent yields. The condensations take place under mild conditions and the isolation of the products is simple. 相似文献
7.
Phosphonium salts immobilized on silica gel have been found to be both micellar and phase-transfer catalysts. They are able to exchange their parent anions with the anions present in an aqueous solution and promote, in catalytic amounts, the decarboxylation of 6-nitrobenzisoxazole-3-carboxylate to give 2-cyano-5-nitrophenolate, a test for micellar catalysis. 相似文献
8.
Federica Benvenuti Carlo Carlini Mario Marchionna Anna Maria Raspolli Galletti Glauco Sbrana 《先进技术聚合物》1999,10(9):554-560
Brominated and chloromethylated styrene–divinylbenzene resins were used for the synthesis of polymer‐bound dithio‐β‐diketones, obtained by anchoring the chelate ligand through the central position. The heterogenized dithio‐β‐diketone ligand was subsequently reacted either as sodium salt with a Ni(II) phosphino derivative or directly with a Ni(0) complex in the presence of a free phosphine and activated in situ with an aluminum co‐catalyst for the selective dimerization of propylene to 2,3‐dimethylbutenes. The hetetogenized catalysts so obtained showed, particulary when prepared starting from chloromethylated styrene/divinylbenzene resins, very high activity and selectivity towards 2,3‐dimethylbutenes. Moreover, the above catalysts, at least under the adopted reaction conditions, did not display any appreciable metal leaching during the catalytic cycle, thus working as really heterogeneous systems. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
9.
A variety of novel O,O‐Diphenyl N‐(trichlorogermanyl)propiono‐α‐aminophosphonates were synthesized by the reaction of β‐(trichlorogermanyl) propionyl chloride with diphenyl α‐aminophosphonates in the presence of triethylamine. The structures of all of the products were confirmed by 1H‐NMR spectroscopy, elemental analyses, and IR spectroscopy. Data of 1H‐NMR and IR spectroscopic determinations indicated the title compounds to be pentacoordinated organogermanium compounds. The results of bioassay showed that some of the title compounds possess potential anticancer activity. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 5–8, 1999 相似文献
10.
SO3H‐functionalized halogen‐free ionic liquids were prepared and used as efficient and recyclable catalysts for the synthesis of α‐aminophosphonates at room temperature via the one‐pot three‐component condensation reaction in aqueous media with good yields of 80–96%. The postprocessing was simple, and the catalysts could be reused at least six times without noticeably decreasing the catalytic activity. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:546–550, 2010; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20644 相似文献
11.
Matthew R. Wood Ivan Bernal Roger A. Lalancette 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(1):48-51
α‐Pyrrolidinovalerophenone (α‐PVP), a dangerous designer drug, is now being marketed around the world as a harmless `bath salt', when in reality it is a powerful β‐ketone phenethylamine stimulant. A sample of the free base from a recent law‐enforcement seizure was crystallized as the HCl salt [systematic name: 1‐(1‐oxo‐1‐phenylpentan‐2‐yl)pyrrolidin‐1‐ium chloride 0.786‐hydrate], C15H22NO+·Cl−·0.786H2O. In the crystal structure, the propyl chain is nearly perpendicular to both the phenyl ring and the carbonyl group. The hydrogen‐bonding scheme involves the quaternary N atom, the Cl− anion and the partially occupied (0.786) water molecule, forming centrosymmetric dimers. 相似文献
12.
R. T. Swiger 《Journal of polymer science. Part A, Polymer chemistry》1975,13(7):1555-1564
Crystal polystyrene was alkylated with N-methylolacetamide (CH3CONHCH2OH), boron trifluoride being used as the catalyst. A linear relationship between degree of N-methyleneacetamide substitution and the glass transition temperature Tg of the polystyrene was observed. The Tg values ranged from 104°C for 0% amidization to 125°C for 20% amidization. The critical strain εc of these materials was measured at room temperature in air, hexane, and oil (50–50, a cottonsed oil–oleic acid) and an increase in the εc above which crazing occurs was observed as the degree of alkylation increased. Thermogravimetric analysis (TGA) of the amidized polystyrenes in air at 250°C showed these materials to become more stable as the amount of N-methylene substitution increased. Tensile data show that the amidized polystyrene, although stronger than the unsubstituted material, exhibits the same elongation at break and tensile modulus. 相似文献
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14.
Carlo Naddeo Liberata Guadagno Domenico Acierno Vittoria Vittoria 《Macromolecular Symposia》1999,138(1):209-214
In this work we compare calorimetric and X-ray diffraction experiments realized on annealed sPS in helical γ forms resulting by different treatements: From clathrate δ form and from interaction of amorphous sample with acetone. The experimental results show that the γ form obtained by acetone converts into the more ordered final α” form modification; while the γ form, obtained by thermal treatments of δ form, transforms into the poorly ordered final α' form. 相似文献
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16.
Synthesis of new optically active α,α′,β‐trisubstituted‐β‐lactones as monomers for stereoregular biopolyesters 下载免费PDF全文
Rima Belibel Christel Barbaud 《Journal of polymer science. Part A, Polymer chemistry》2015,53(22):2586-2597
Various optically active (4R)‐alkyloxycarbonyl‐3,3‐dialkyl‐2‐oxetanones as monomers were synthesized from L‐(S)‐malic acid in six steps to prepare a new family of stereopolyesters for biomedical applications. The synthesis began with an esterification followed of a dialkylation in the aim to introduce hydrophobic groups as methyl or reactive group as allyl. Then, a saponification has permitted to obtain the corresponding diacids that reacted with appropriate alcohols to furnish different monoesters. The last and most important step was activation of hydroxyl group of monoesters with the asymmetric carbon configuration inversion according to the Mitsunobu reaction. Thus, this reaction has provided lactones from monoesters with 100% enantiomeric excess which was confirmed by 1H NMR and by the synthesis of corresponding isotactic and semicrystalline homopolyesters. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2586–2597 相似文献
17.
Stefan Beck Adrian R. Brough Manfred Bochmann 《Journal of molecular catalysis. A, Chemical》2004,220(2):275-284
Homoleptic and mixed -zirconium phosphonates (ZrPs) -Zr(O3PR)2 (R = Me, Bun, Bui, Hex, Oct and Ph) and -Zr(O3PR1)2−x(O3PR2)x were readily prepared in high yields from zirconyl choride and the corresponding phosphonic acids in suitable solvent mixtures under hydrothermal conditions at low fluoride concentrations. They form crystalline aggregates consisting of platelets from ca. 10–20 monolayers thickness, with well-defined surface structures. Impregnation with Cp2ZrCl2 by sublimation or slurry methods provided the first examples of ZrP-supported alkene polymerization catalysts. Crystal morphology and interlayer spacing are unaffected by the impregnation process. Solid-state NMR spectroscopy provides evidence for the integrity of the adsorbed metallocene structure. Covalent attachment of Cp*ZrCl3 to functionalized ZrPs of the type -Zr(O3PR1)1.8(O3PCnH2nOH)0.2 is similarly possible. The new catalysts polymerize ethene with good to excellent activities under mild conditions, even at remarkably low methylalumoxane/zirconocene ratios of 10:1. The polymer is obtained as free-flowing particles, which reflect the morphology of the catalyst supports. 相似文献
18.
η3-Allylnickel alkoxides {η3-C3H5NiOR}2 (R = Me, Et, i-Pr, Ph, SiPh3) may be activated by gaseous boron trifluoride (BF3) to give active catalysts for the dimerization of propene in homogeneous phase. In CH2Cl2 at ?20 °C catalytic turnover numbers of 5000 mol propene(mol Ni)?1h?1 were measured. The nature of the OR group influences both the catalytic activity and the oligomerization product distribution. The ratio of methylpentenes to dimethylbutenes in the dimer fraction may be controlled by the presence of additional phosphine ligands at the nickel atom. The nickel alkoxide precursor was heterogenized on alumina to give {Al2O3}–O–Ni–(η3-C3H5). Subsequent activation using gaseous BF3 generates a powerful heterogeneous olefin dimerization catalyst which converts 50 × 103 mol propene (mol Ni)?1 at ?10° to ?5°C in a batchwise process and 143 × 103 mol propene (mol Ni)?1 continuously to give 75% dimers and 25% higher oligomers. The solvent-free treatment of oxide supports, e.g. alumina or silica, with gaseous BF3 produces strong ‘solid acids’. The activated hydroxyl groups on the support surface serve as effective anchor sites for organometallic complexes to form heterogenous catalysts. By reaction of Ni(cod)2 with {Al2O3}O(BF3)H or {SiO2}O(BF3)H, η1, η2-cyclo-octenylnickel–O fragments may be fixed to the surface. In the absence of halogenated solvents, the resulting catalysts, e.g. {SiO2}O–(BF3)–Ni–(η1, η2-C8H13), dimerize propene continuously at +5°C at the rate of 800 × 103 mol liquid propene (mol Ni)?1. 相似文献
19.
Eiji Ihara Takao Wake Naoki Mokume Tomomichi Itoh Kenzo Inoue 《Journal of polymer science. Part A, Polymer chemistry》2006,44(19):5661-5671
α,α‐Dibromotoluene 1 was found to be polymerized by the reaction with excess Mg to give poly(phenylmethylene)s 2 , whose main chains were partially dehydrogenated to carbon–carbon double bonds (C?C). The C?Cs in 2 can be brominated by treatment with Br2. The polymerization mechanism was presumed to include the formation of Grignard reagents of various species with benzylic C? Br bonds and the nucleophilic attacks of the Grignard reagents to various compounds with benzylic C? Br bonds. Copolymerization of 1 with dichlorodimethylsilane successfully proceeded. Mg/Cu‐mediated copolycondensation of 1 with 1,6‐dibromohexane proceeded to give polymers that have similar compositions to those of random copolymers of ethylene and styrene. © 2006Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5661–5671, 2006 相似文献