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1.
Attachment of phosphites to styrene copolymers is described which are used as rhodium hydroformylation catalysts. The influence of the chain loading on the activity and complex formation of three types of copolymer-bound rhodium hydroformylation catalysts in comparison with their low molecular weight analogues has been studied. The catalytic activity of the polystyrene-bound system with the most bulky phosphite, the first system studied, is identical to that of the low molecular weight analogue. The catalysts show a high activity towards the hydroformylation of the otherwise unreactive cyclooctene. It was found that only one phosphite is coordinated to the rhodium complex in its active form. An equilibrium between this complex and an inactive complex without phosphite ligands prohibits its use in continuous flow reactors. Secondly, as polymer support a perfectly random copolymer of styrene and less bulky 3,3′,5,5′-tetra-tert-butylbiphenyl-2,2′-diyl p-vinylphenylphosphite was used. The chain loading α of this copolymer with phosphite ligands has a large influence on the complex formation of the catalyst. With high chain loadings moderately active bis-phosphite catalysts are formed. Low chain loadings give active, easily accessible, monophosphite complexes. The active species in the hydroformylation of sterically hindered alkenes is a mono-phosphite rhodium complex. The activity of the copolymer-bound catalyst towards the hydroformylation of cyclooctene is found to be as high as the activity of its low molecular weight analogue. For styrene, this polymer catalyst yields a slower catalyst than the low-molecular weight analogue. The third part demonstrates that silica-grafted polymer-bound phosphite modified rhodium complexes can be used in continuous flow reactors. The hydroformylation of styrene was carried out at moderate pressure (pCO/H2 = 3 MPa) and temperature (T = 100°C), yielding constant conversions over a period of at least ten days. These positive results were obtained in benzene as a solvent and for a ligand to rhodium ratio of only four. 相似文献
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Yu. B. Kagan O. L. Butkova G. A. Korneeva S. M. Loktev 《Russian Chemical Bulletin》1985,34(8):1565-1567
Conclusions The introduction of an organosilicon fragment into the hydrocarbon chain connecting the phosphorus atoms in a diphosphine does not affect the properties of this compound as a modifier of cobalt carbonyl catalyst for olefin hydroformylation. The use of O-methyl-bis(dibutylphosphinoethyl)methylsilane as the modifier leads to the formation of an active and selective cobalt carbonyl catalyst for olefin hydroformylation.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1714–1716, August, 1985. 相似文献
3.
Yao Zhang Jie Li Guoyu Ren Baofu Qin Haixia Ma 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(6):485-490
Azole compounds have attracted commercial interest due to their high bactericidal and plant‐growth‐regulating activities. Uniconazole [or 1‐(4‐chlorophenyl)‐4,4‐dimethyl‐2‐(1H‐1,2,4‐triazol‐1‐yl)pent‐1‐en‐3‐ol] is a highly active 1,2,4‐triazole fungicide and plant‐growth regulator with low toxicity. The pharmacological and toxicological properties of many drugs are modified by the formation of their metal complexes. Therefore, there is much interest in exploiting the coordination chemistry of triazole pesticides and their potential application in agriculture. However, reports of complexes of uniconazole are rare. A new cobalt(II) complex of uniconazole, namely dichloridotetrakis[1‐(4‐chlorophenyl)‐4,4‐dimethyl‐2‐(1H‐1,2,4‐triazol‐1‐yl‐κN4)pent‐1‐en‐3‐ol]cobalt(II), [CoCl2(C15H18ClN3O)4], was synthesized and structurally characterized by element analysis, IR spectrometry and X‐ray single‐crystal diffraction. The crystal structural analysis shows that the CoII atom is located on the inversion centre and is coordinated by four uniconazole and two chloride ligands, forming a distorted octahedral geometry. The hydroxy groups of an uniconazole ligands of adjacent molecules form hydrogen bonds with the axial chloride ligands, resulting in one‐dimensional chains parallel to the a axis. The complex was analysed for its antifungal activity by the mycelial growth rate method. It was revealed that the antifungal effect of the title complex is more pronounced than the effect of fungicide uniconazole for Botryosphaeria ribis, Wheat gibberellic and Grape anthracnose. 相似文献
4.
《Journal of Coordination Chemistry》2012,65(24):4180-4193
AbstractA series of six new mononuclear Schiff base complexes, 1–6 of cobalt(III) of the general formula, [CoLX] or its adduct with methanol, is reported. The pentadentate Schiff base ligand (H2L) was obtained by the condensation of N-(3-aminopropyl)-N-methylpropane-1,3-diamine with 1-(2-hydroxyphenyl)ethanone (H2L1) or 1-(2-hydroxyphenyl)propan-1-one (H2L2). X stands for the pseudohalides, N3–, N(CN)2? , and NCS–. The complexes have been synthesized by the reaction of equimolar amounts of cobalt(II) nitrate with H2L1 or H2L2 in the presence of the respective pseudohalide in methanol medium. All the complexes have been characterized by microanalytical, spectroscopic, single crystal XRD (except 3), and other physicochemical studies. Structural studies reveal that the central Co(III) ion in 1, 2, 4, 5, and 6 adopts a distorted octahedral geometry with a CoN4O2 chromophore. Weak intermolecular H-bonding and/or π-interactions are operative in these complexes to bind the molecular units. The antimicrobial activity of all the complexes and their constituent Schiff bases has been tested against some common bacteria and fungi. 相似文献
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Hu LL Jia ZQ Tao J Huang RB Zheng LS 《Dalton transactions (Cambridge, England : 2003)》2008,(44):6113-6116
Solvothermal reaction of Co(OAc)2.4H2O with H4L (H4L = 2-((2-hydroxybenzylidene)amino)-2-hydroxymethylpropane-1,3-diol) in MeCN gave a mixed-valence pentanuclear cobalt complex [Co5(HL)2(H2L)2(OAc)2].2.5H2O. Crystal structural analysis revealed that two Co(III) ions were linked to a central triangular Co(II) core through HL(3-) and H2L(2-) hydroxyl groups. Magnetic measurements showed interesting magnetic properties that were assigned to spin-orbital coupling and ferromagnetic exchange interactions. 相似文献
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《Journal of Coordination Chemistry》2012,65(15):2612-2622
Four new mononuclear complexes, [Ni(L1)(NCS)2] (1), [Ni(L2)(NCS)2] (2), [Co(L1)(N3)2]ClO4 (3), and [Co(L2)(N3)2]ClO4 (4), where L1 and L2 are N,N′-bis[(pyridin-2-yl)methylidene]butane-1,4-diamine and N,N′-bis[(pyridin-2-yl)benzylidene]butane-1,4-diamine, respectively, have been prepared. The syntheses have been achieved by reaction of the respective metal perchlorate with the tetradentate Schiff bases, L1 and L2, in presence of thiocyanate (for 1 and 2) or azide (for 3 and 4). The complexes have been characterized by microanalytical, spectroscopic, single crystal X-ray diffraction and other physicochemical studies. Structural studies reveal that 1–4 are distorted octahedral geometries. The antibacterial activity of all the complexes and their constituent Schiff bases have been tested against Gram-positive and Gram-negative bacteria. 相似文献
9.
Yun Shen Jianhua Zhu Hongxia Chen Dan Huang 《Research on Chemical Intermediates》2016,42(4):2909-2918
A modified benzophenone UV-absorber containing reactive group (4-(4,6-dichloro-1,3,5-triazin-2-yloxy)-2-hydroxyphenyl)phenyl)methanone (UV-DTHM) has been prepared in good yield from the nucleophilic substitution reaction of 2,4-dihydroxy benzophenone with 2,4,6-trichlorotriazine, catalyzed by 1.3 equiv. NaOH. The most favorable reaction conditions (the catalyst dosage, the mole ratio of the reactants, and reactive time) were selected. The compound was characterized by IR spectroscopy, 1H NMR, 13C NMR, mass spectrometry, elemental analysis, and single crystal X-ray diffraction. The crystal monoclinic, space group C c with the unit cell parameters a = 3.987(2), b = 30.688(16), c = 12.423(6) Å and α = 90.00, β = 92.117(15), γ = 90.00º, Z = 4, R = 0.0620. wR(F 2) = 0.1589. The crystal structure reveals that 2,4,6-trichlorotriazine is boned to 4-seat hydroxyl of 2,4-dihydroxy benzophenone and a intramolecular hydrogen bond is formed with hydrogen of 2-hydroxyl and oxygen of carbonyl group. Moreover, thermogravimetric analysis (TGA) of UV-DTHM was studied, showing two distinct endothermic peaks at temperatures of 281.5 and 358.5 °C. The molar absorption coefficient of UV-DTHM is 1.6 × 104 and 6.3 × 103 at 268 and 330 nm, respectively, and shows excellent ultraviolet absorption property. 相似文献
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Peter T. Ndifon Moise O. Agwara Awawou G. Paboudam Divine M. Yufanyi Jean Ngoune Agustín Galindo Eleuterio Álvarez Aminou Mohamadou 《Transition Metal Chemistry》2009,34(7):745-750
A novel one-dimensional zigzag coordination polymer, dinitrodiaqua-bis(hexamethylenetetramine)cobalt(II) was synthesised and characterised, and the structure was determined by single-crystal X-ray diffraction. The compound has a chain structure with each cobalt atom covalently bonded to two nitrate ions, two water molecules and two HMTA molecules, giving a slightly distorted octahedral geometry about the cobalt atom. Each HMTA ligand uses two of its N atoms to bond to two cobalt atoms giving an approximately bent Co–HMTA–Co configuration. Each chain is hydrogen bonded through OH···N and OH···O interactions with neighbouring chains leading to an overall polymer structure. Thermal studies show significant mass loss corresponding to the loss of the coordinated water molecules and the decomposition of both the nitrate ions and the HMTA. 相似文献
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《Journal of Coordination Chemistry》2012,65(11):1962-1979
Three complexes based on fluconazole, namely, {[Co2(HFlu)(dpa)2(H2O)2]·H2O}n (1), {[Zn(HFlu)(IPA)]·H2O}n (2), and {[Mn(HFlu)2(IPA)(H2O)]·H2O}n (3) (HFlu?=?fluconazole, 2-(2,4-difluoro-phenyl)-1,3-bis(1,2,4-triazol-1-yl)-propan-2-ol; H2dpa?=?diphenic acid; H2IPA?=?isophthalic acid) have been synthesized. Single-crystal X-ray analysis revealed that 1 is a 2-D-network framework containing a trinuclear Co(II) unit, 2 is a 3-D framework, and 3 is 1-D double chain structure with a Mn2 metallocyclic core. The complexes have also been characterized by elemental analyses, IR, UV/vis and fluorescence spectroscopy, and thermal gravimetry. The phase purity of these polymers has been confirmed via powder X-ray diffraction. 相似文献
13.
D. F. Xu Z. H. Shen Y. Shi Q. He Q. C. Xia 《Russian Journal of Coordination Chemistry》2010,36(6):458-462
This work reports the synthesis and biological activity of the copper complex with 2–thenoyltrif-luoroacetone (HTTA). The
complex was characterized by elemental analysis, infrared spectroscopy, and thermogravimetric analysis. The crystal structure
was determined by single-crystal X-ray diffraction. The complex exists as a parallelogram with four coordination sites occupied
by the carbonyl oxygen atoms from HTTA. The antibacterial activity test shows that the complex exhibits better antibacterial
ability against Escherichia coli and Staphylociccus aureus (MIC were about 180, 150 μg/ml, respectively) and can be considered as broad-spectral antimicrobial. The antitumor activity
of the copper(II) complex is tested by methyl thiazolyl tetrazolium assays against human Leukemia cells K562. The copper(II)
complex exhibits potent antitumor effects against K562 cell lines. The IC50 value of the complex is about 0.01 μg/ml. The research shows that the complex can inhibit K562 tumor cell growth and generation
and induce apoptosis. The inhibition ratio is accele by increasing the dosage and has a significant positive correlation with
medication dosage. 相似文献
14.
L. B. Belykh N. I. Skripov L. N. Belonogova V. A. Umanets F. K. Schmidt 《Kinetics and Catalysis》2010,51(1):42-49
The applicability of elemental phosphorus as a modifier of palladium catalysts for hydrogenation was demonstrated, and the
conditions for the synthesis of nanoparticles that are highly efficient in hydrogenation catalysis were optimized. The modifying
effect of elemental phosphorus depends on the P/Pd ratio; it is associated with changes in the catalyst dispersity and the
nature of the formed nanoparticles containing various palladium phosphides (PdP2, Pd5P2, and Pd6P) and Pd(0) clusters. The main stages of the formation of palladium catalysts for hydrogenation were determined, and a model
of an active catalyst, in which the Pd6P phosphide is the core of a nanoparticle and Pd(0) clusters form a shell, was proposed. 相似文献
15.
Synthesis and crystal structure of polymer cobalt(II) complex, 1,2,4,5-benzenetetracarboxylate hexaimidazole tetraaqua cobalt (II) tetrahydrate 总被引:1,自引:0,他引:1
The crystal structure of the title complex {[Co(TCB)2/2-(IMI)2(H2O)2][Co(IMI)4(H2O)2] } (H2O)4 (where TCB = 1,2,4,5-benzenetetracarboxylic anion; IMI = imidazole) has been determined by X-ray diffraction method. Crystal data for {[Co(TCB)2/2(IMI)2(H2O)2][Co(IMI)4(H2O)2]}-(H2O)4: triclinic, space group P 1, a = 1.0647(2) nm, b = 1.1165(1)nm,c = 1.00361(1)nm,α = 91.56(1)°,β = 111.34(1)°, γ = 115.642(10)°, V = 0.9772(3) nm5, Z = 1. The polymer cobalt (II) complex has a novel three-dimension network structure. Co(1) atom and Co(2) atom both are coordinated in an octahedral arrangement and located in the center of the coordination anion and the center of the coordination cation, respectively. Moreover four carboxyl groups of TCB are divided into two types, two para-carboxyl groups bridge Co(1) atom in monodentate fashion and other two para-carboxyl groups are in free. 相似文献
16.
将有机物2,5-二溴对苯二甲酸(H2L1)作为主配体,2,2′-联吡啶(L2)、1,10-菲咯啉(L3)分别作为辅配体,通过溶剂热法与一水硫酸锰、六水合硝酸钴分别反应得到配合物[Mn2(L1)2(L2)2(H2O)2]n (1)和[CO2(L1)2(L3)2(H2O)2]n (2)。通过单晶 X射线衍射法、荧光光谱、热重分析等测试手段对这 2种配合物进行分析研究。结果表明配合物 1是由 Mn2+配位连接 L12-与 L2形成无限延伸的二维网络状结构,各层在分子间氢键和π-π堆积作用下形成了三维网络状结构。配合物2是由CO2+配位连接L12-和L3形成的无限延伸的二维网络状结构,各层在分子间氢键和π-π堆积作用下形成三维网络状结构。且这2种配合物均具有良好的荧光性和热稳定性,配合物1和2的最大发射波长分别为355和365 nm。 相似文献
17.
将有机物2,5-二溴对苯二甲酸(H2L1)作为主配体,2,2′-联吡啶(L2)、1,10-菲咯啉(L3)分别作为辅配体,通过溶剂热法与一水硫酸锰、六水合硝酸钴分别反应得到配合物[Mn2(L1)2(L2)2(H2O)2]n (1)和[Co2(L1)2(L3)2(H2O)2]n(2)。通过单晶X射线衍射法、荧光光谱、热重分析等测试手段对这2种配合物进行分析研究。结果表明配合物1是由Mn2+配位连接L12-与L2形成无限延伸的二维网络状结构,各层在分子间氢键和π-π堆积作用... 相似文献
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Synthesis,crystal structure and cytotoxic activity of tricyclohexyltin complexes of benzenedioxyacetic acids 下载免费PDF全文
Two new bis(tricyclohexyltin)benzenedioxyacetates, 1,x‐C6H4[OCH2CO2Sn(c‐C6H11)3]2 ( 1 : x = 3; 2 : x = 4), have been synthesized and characterized by means of elemental analysis, infrared and NMR (1H, 13C and 119Sn) spectra and single‐crystal X‐ray diffraction. Compound 1 ?H2O?CH3OH is a binuclear tin complex containing a four‐coordinated tin and a five‐coordinated tin and linked by an R33(16) hydrogen bond into a one‐dimensional supramolecular chain. Compound 2 is a two‐dimensional coordination polymer which is formed as a result of anisobidentate bridging coordination action of the two carboxylate units of the ligand. Interestingly the two‐dimensional coordination polymer contains 34‐membered macrocycles each of which is comprised of four tricyclohexyltin units. Both compounds have potent in vitro cytotoxic activity against three human tumor cell lines: HeLa, MCF‐7 and CoLo 205. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Agnieszka Pladzyk Katarzyna Baranowska Patrycja Hapter 《Transition Metal Chemistry》2010,35(3):373-379
The synthesis and characterization of four new Co(II) tri-tert-butoxysilanethiolates with 3- and 4-methylpyridine are reported. Mononuclear complexes have been obtained in reactions with
bimetallic [Co{μ-SSi(O
t
Bu)3}{SSi(O
t
Bu)3}(NH3)]2 as a Co(II) substrate. The new compounds have been characterized by single-crystal X-ray structure determination, UV–vis
and FT-IR spectroscopy and elemental analysis. The complexes are tetra- and penta-coordinated with CoN2S2 and CoNO2S2 cores, respectively. 相似文献