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1.
A simple synthesis of 1,2,3,5-tetrasubstituted pyrrole derivatives from the reaction of enaminone withα-haloketones,under solvent-free conditions,is described. 相似文献
2.
Changkun Xia Kai Yang Fan Wu Xiaoqing Lu Yuanyuan Min Jimin Xie 《Journal of Coordination Chemistry》2017,70(14):2510-2519
Two coordination complexes based on H4btec and H2bibzim (H4btec = 1,2,3,5-benzenetetracarboxylic acid, H2bibzim = 2,2′-bibenzimidazole), [Ni(H2bibzim)3]2(btec) (1) and [Zn(H2bibzim)(btec)0.5]n (2), have been synthesized by hydrothermal methods and characterized by single-crystal X-ray diffraction. Complex 1 is composed of [Ni(H2bibzim)3]2+ with free btec4? as counter anion. In 2, the btec4? ligands bridge the Zn(II) ions into a 1-D chain with H2bibzim as auxiliary chelating ligands. Interesting supramolecular structures were demonstrated due to the existence of hydrogen bonding as well as π?π interactions in the two different complexes. The H2bibzim ligands act as a 2-connected spacer in both complexes. However, in 1, the [Ni(H2bibzim)3]2+ cations act as 3-connected nodes, hydrogen bonded with the 6-connected btec4? ligands into a 3-D framework with (3,6)-connected topology Schläfli symbol as (4.6.8)(42.6)(43.64.87.10). As for 2, Zn serves as a 3-connected node with btec4? as a 6-connected node, leading to a 2D (3,6)-connected hydrogen bonding kgd topology sheet with Schläfli symbol of (43)2(46.66.83). Thermal stabilities and photoluminescent properties of 1 and 2 were also studied. 相似文献
3.
Yah Chao WU Xiao Mao ZOU Fang Zhong HU Hua Zheng YANG 《中国化学快报》2005,16(9):1143-1146
A series of novel 5-sulfoxide-substituted pyrazolo[5,1-d] [1,2,3,5]tetrazin-4(3H)ones 4a-j were designed and efficiently synthesized via a diazotization of 5-amine-3-methylsulfinyl- 1H-pyrazole, followed by cycloaddition with aryl isocyanate. A possible reaction mechanism is outlined and discussed. These new compounds exhibit some biological activity as preliminary bioassay indicated. Their structures were confirmed with ^1H NMR, IR and elemental analysis. 相似文献
4.
《Tetrahedron: Asymmetry》2001,12(19):2715-2720
Homochiral primary amines, amino alcohols and α-amino esters have been reacted with 2-propynyl-1,3-dicarbonyl compounds under gold catalysis leading to 1,2,5-trisubstituted 3-acylpyrrole derivatives in moderate to high yields and high enantiomeric excess. 相似文献
5.
The base-induced formal [4 + 3] annulation reactions of N-(ortho-chloromethyl)aryl amides with nitrones or hydrazonoyl chlorides have been reported. When nitrones are used as the 1,3-dipole, the corresponding reaction afforded a series of 1,2,3,5-tetrahydrobenzo[e][1,2,4]oxadiazepine derivatives. Highly functionalized 2,3-dihydro-1H-benzo[e][1,2,4]triazepine derivatives were also synthesized via an unprecedented tandem aza-Michael addition/rearrangement aromatization between N-(ortho-chloromethyl)aryl amides and hydrazonoyl chlorides. 相似文献
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7.
Synthesis and characterization of di- and trivalent pyrazolylborate β-diketonates and cyanometalates
Tang M Li D Mallik UP Zhang YZ Clérac R Yee GT Whangbo MH Mungalimane A Holmes SM 《Inorganic chemistry》2011,50(11):5153-5164
The syntheses, structures, and magnetic properties of a series of di- and trivalent hydridotris(3,5-dimethylpyrazol-1-yl)borate (Tp*) cyanomanganates are described. Treatment of tris(acetylacetonate)manganese(III) [Mn(acac)(3)] with KTp* and tetra(ethyl)ammonium cyanide affords [NEt(4)][(Tp*)Mn(II)(κ(2)-acac)(CN)] (1), as the first monocyanomanganate(II) complex; attempted oxidation of 1 with iodine affords {(Tp*)Mn(II)(κ(2)-acac(3-CN))}(n) (2) as a one-dimensional chain and bimetallic {[NEt(4)][(Tp*)Mn(II)(κ(2)-acac(3-CN))](2)(μ-CN) (3) as the major and minor products, respectively. A fourth complex, [NEt(4)][(Tp*)Mn(II)(η(2)-acac(3-CN))(η(1)-NC-acac)] (4), is obtained via treatment of Mn(acac(3-CN))(3) with KTp* and [NEt(4)]CN, while [NEt(4)](2)[Mn(II)(CN)(4)] (5) was prepared from manganese(II) trifluoromethanesulfonate and excess [NEt(4)]CN. Tricyanomanganate(III) complexes, [cat][(Tp*)Mn(III)(CN)(3)] [cat = NEt(4)(+), 7; PPN(+), 8], are prepared via sequential treatment of Mn(acac(3-CN))(3) with KTp*, followed by [NEt(4)]CN, or [cat](3)[Mn(III)(CN)(6)] with (Tp*)SnBu(2)Cl. Magnetic measurements indicate that 1, 2, and 4 contain isotropic Mn(II) (S = (5)/(2); g = 2.00) centers, and no long-range magnetic ordering is found above 1.8 K. Compounds 7 and 8 contain S = 1 Mn(III) centers that adopt singly degenerate spin ground states without orbital contributions to their magnetic moments. 相似文献
8.
《Tetrahedron letters》1987,28(51):6473-6474
The reaction of diphenyltin bis(dithiophosphates) with N-bromo- and N-iodosuccinimides afforded corresponding thiophosphorosulfenyl bromides and iodides, which reacted with a variety of nucleophiles such as thiol, dithiocarboxylic acid, amine and olefin to give novel unsymmetrical disulfides, sulfenamides and dithiophosphoric acid esters. 相似文献
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10.
Andreas Richter Steffen Howitz Dirk Kuckling Katja Kretschmer Karl-Friedrich Arndt 《Macromolecular Symposia》2004,210(1):447-456
This paper describes automatically and electronically controlled valves and microvalves based on smart hydrogels. The operating performance of such devices will be discussed in dependence on various design parameters. Furthermore, it will be shown that hydrogel based valves are showing an outstanding possibility of miniaturization, a leakage free switching behavior up to a pressure drop of 8.4 bar, and a pronounced particle tolerance. 相似文献
11.
A series of six-coordinate “half-sandwich” zirconocene phosphates and phosphonates have been synthesized by the reaction of
Cp2ZrCl2 with (diphenyl-, dibenzyl-)phosphate and methylphenylphosphinic acid under different conditions. All of the complexes were
characterized by elemental analysis, FT-IR and NMR (1H, 13C) spectroscopy. Except for complex 3, the structures of complexes 1, 2, 4, 5, and 6 were confirmed by X-ray crystallography. The structure analyses reveal that complexes 1, 2, and 3 are trinuclear complexes with fascinating μ3-oxygen bridging ligands, central to a Zr–O backbone (Cp2ZrCl2:ligand is 1:1) while complexes 4, 5, and 6 are centrosymmetric dinuclear complexes built up about the trapezoidal Zr2(μ2-OH)2 unit (Cp2ZrCl2:ligand is 1:2). 相似文献
12.
M. A. Bazhenova S. S. Bogush A. G. Herbst T. V. Demeshchik Yu. G. Komarovskaya V. S. Kurova M. D. Reshetova A. D. Ryabov E. S. Ryabova Yu. N. Frrsova 《Russian Chemical Bulletin》1996,45(10):2445-2451
Absract Simple methods have been developed for the preparation of a series ofn-alkylferrocenes H(CH2)
n
Fc (n = 3, 5–8, or 12) based on Friedel-Crafts acylation of ferrocenes followed by reduction of the corresponding ketones with Zn amalgam. The properties of H(CH2)
n
Fc and the corresponding ferrocenium ions in micellar aqueous solutions and the behavior of water-soluble cations H(CH2)
n
Fc+ in the absence of micelles were studied by cyclic voltammetry. In all cases, the formal redox potentials of ferrocenes (E
o) increase linearly asn increases up to 8. Whether micelles are present or not, the corresponding correlation equation has the following form:E
o= + n, where = 29 mV in all cases. The synthesis of (±)-1-ethyl-2-methylferrocene from racemic -dimethylaminoethylferrocene is reported.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2575–2581, October 1996. 相似文献
13.
Zhong Zhou CHENG Ze Hui JIA Yan CHEN Li Ying CHEN Hua LI 《中国化学快报》2006,17(8):1057-1060
Nicorandil [N-(2-hydroxyethyl)-nicotinamide nitrate NIC] is a novel kind of compound in the treatment of angina pectoris. NIC can be degraded easily in storage. The degradation products include N-(2-hydroxyethy) nicotinamide (HN), nitrate ion (NI), and ni… 相似文献
14.
A Trichosanthin gene was cloned from Trichosanthes kirilowii genomic DNA by polymerase chain reaction (PCR). Nucleotide sequence data indicated that we obtained the coding region of the mature Trichosanthin peptide as well as its signal peptide at the N-terminus. Comparisons of our sequence with the previously reported nucleotide sequences of this gene showed 99.25% homology, yet there were notable differences between the previously reported amino acid sequence and our deduced result. This gene was subcloned into a highlevel expression plasmid (pJLA502) of E. coli under the control of a P_RP_L promoter, and we observed the gene product after temperature induction. The gene was further cloned into plant intermediate vector pE3 under the control of a CaMV 35S promoter, and transferred into a tobacco genome using the agrobacterium-mediated gene transfer system. Western blotting analysis of the protein extracted from Escherichia coli and transgenic tobacco plants proved that the Trichosanthin gene has been 相似文献
15.
Zh. A. Krasnaya E. O. Tret��yakova V. V. Kachala S. G. Zlotin 《Russian Chemical Bulletin》2011,60(10):2014-2020
Reactions of N-acetyl- and N-benzyl-4-piperidones with aminal of ??-dimethylaminoac-rolein yielded ketocyanines bearing piperidine cycle. Reaction of 3-dimethylamino-1,1,3-trimethoxypropane with 1-acetylpiperidin-4-ylidenemalononitrile in the presence of ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4), resulted in cross-conjugated ??,???-dimethylamino dinitrile. Protonation of ketocyanines bearing N-acetyl- and N-benzyl-piperidine cycles with Et2O·HBF4 (1 equiv.) furnished piperidinium salts, while protonation of the latter with Et2O·HBF4 (2 equiv.) afforded doubly charged 4-hydroxypolymethine salts. Unlike protonation, reaction of 3,5-bis(3-dimethylaminoprop-2-enylidene)-1-acetylpiperidin-4-one with Me2SO4 involved only the oxygen atom and led to a singly charged 4-methoxypolymethine salt. Methylation of 3,5-bis(3-dimethylaminoprop-2-enylidene)-1-benzylpiperidin-4-one with Me2SO4 (1 equiv.) involved cyclic nitrogen atom and resulted in piperidinium salt; heating of the latter with the excess of Me2SO4 afforded doubly charged bis-methoxysulfonate. Starting from 4-methoxytetrahydropyridinium salts, meso-methoxythiapentacarbocyanine dyes were synthesized. 相似文献
16.
Two dyads of eosin and porphyrin linked with a semi-rigid (-CH2phCH2-) or flexible (-(CH2)4-) bridge and their reference model compounds were synthesized and characterized The intermoleccular interaction and intramolecular photoinduced singlet energy transfer and electron transfer were studied by their absorp tion spectra,fluorescence emission,excitation spectra and fluorescence lifetime The model compounds,ethyl ester of eosm (EoEt) and porphyrin (PorEt),could form complexes in the ground state.When the eosin moieties in dyads were excited,they could transfer some singlet energy to the porphyrins; in the meantime,they could also ndsce electron transfer between two chromophores.Exciting the porphyrin moieties in dyads could induce electron transfer from eosin moieties to porphyrin moieties.The efficiencies (EnT,ET) and rate constants (kEnT,kET) were related to the polarity of solvents and mutual orientation of the two chromophores in dyads. 相似文献
17.
Artamkina G. A. Shilova E. A. Shtern M. M. Beletskaya I. P. 《Russian Journal of Organic Chemistry》2003,39(9):1282-1291
Reactions of p- and m-diiodobenzenes, p,p'-diiodobiphenyl, and 1,3,5-triiodobenzene with anions derived from dicarbonyl(cyclopentadienyl)iron and pentacarbonylmanganese, catalyzed by palladium complexes, provide a successful route to mono-, di-, and trinuclear -aryl iron and manganese complexes. 相似文献
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19.
Seiichiro Ogawa Yasushi Uematsu Satoshi Yoshida Naoko Sasaki Tetsuo Suami 《Journal of carbohydrate chemistry》2013,32(3):471-478
Abstract Pseudo-β-D (D-2) and L-fructopyranose (L-2), 1(S) and (1R)-(1,2/-3,4)-4-C-hydroxymethyl-1,2,3,4-cyclohexanetetrol, have been synthesized, starting from optically active endo-adducts of furan and acrylic acid, following the modified procedure used for the preparation of the racemic modification. It has been demonstrated that the D and L-enantiomers are nearly as sweet as D-fructose, and the former is somewhat sweeter than the latter. 相似文献
20.
Mohamed Tebbaa Ahmed El HakmaouiAhmed Benharref Mohamed Akssira 《Tetrahedron letters》2011,52(29):3769-3771
The aerial part of Dittrichia viscosa yielded two sesquiterpenes, isocostic acid (1) and ilicic acid (2), on multigram scale. These acids are appropriate starting materials for short and facile syntheses of α-eudesmol (5) and cryptomeridiol (6), natural products featuring anti-Alzheimer and anti-spasmodic properties. Compounds 5 and 6 were obtained in three steps in overall yields of 70% and 52%, respectively. 相似文献