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1.
Hong-Ming Wu Ya-Ho Chang Chia-Lin Su Gene-Hsiang Lee Hua-Fen Hsu 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(5):416-420
Vanadium chemistry is of interest due its biological relevance and medical applications. In particular, the interactions of high‐valent vanadium ions with sulfur‐containing biologically important molecules, such as cysteine and glutathione, might be related to the redox conversion of vanadium in ascidians, the function of amavadin (a vanadium‐containing anion) and the antidiabetic behaviour of vanadium compounds. A mechanistic understanding of these aspects is important. In an effort to investigate high‐valent vanadium–sulfur chemistry, we have synthesized and characterized the non‐oxo divanadium(IV) complex salt tetraphenylphosphonium tri‐μ‐<!?tlsb=‐0.11pt>methanolato‐κ6O:O‐bis({tris[2‐sulfanidyl‐3‐(trimethylsilyl)phenyl]phosphane‐κ4P,S,S′,S′′}vanadium(IV)) methanol disolvate, (C24H20P)[VIV2(μ‐OCH3)3(C27H36PS3)2]·2CH3OH. Two VIV metal centres are bridged by three methanolate ligands, giving a C2‐symmetric V2(μ‐OMe)3 core structure. Each VIV centre adopts a monocapped trigonal antiprismatic geometry, with the P atom situated in the capping position and the three S atoms and three O atoms forming two triangular faces of the trigonal antiprism. The magnetic data indicate a paramagnetic nature of the salt, with an S = 1 spin state. 相似文献
2.
Dr. Hai‐Wei Kuai Dr. Xiao‐Chun Cheng Liang‐Dong Feng Xiao‐Hong Zhu 《无机化学与普通化学杂志》2011,637(11):1560-1565
Three new complexes: [M(L)(H2O)] [M = Zn ( 1 ), Co ( 2 ), Ni ( 3 ); H2L = 5‐(pyridin‐2‐ylmethyl)aminoisophthalic acid] were synthesized under hydrothermal conditions at 180 °C and were characterized by elemental analysis, FT‐IR spectroscopy, single‐crystal X‐ray diffraction, and thermogravimetric analysis (TGA). The results of X‐ray diffraction analysis reveal that complexes 1 – 3 are isostructural and crystallize in the monoclinic system with space group P21/c. Each of the complexes displays a (3,3′)‐connected two‐dimensional (2D) wave‐like network with (4,82) topology, within which five‐membered uncoplanar N,N‐chelated metallacycles are shaped. Delicate N–H ··· O and O–H ··· O hydrogen bonding interactions exist in complexes 1 – 3 . Adjacent 2D layers are linked by intermolecular interactions, resulting in the construction of extended metal‐organic frameworks (MOFs) in complexes 1 and 2 . 相似文献
3.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(4):314-318
The unsymmetrical N‐heterocyclic ligand 1‐[(benzotriazol‐1‐yl)methyl]‐1H‐1,3‐imidazole (bmi) has three potential N‐atom donors and can act in monodentate or bridging coordination modes in the construction of complexes. In addition, the bmi ligand can adopt different coordination conformations, resulting in complexes with different structures due to the presence of the flexible methylene spacer. Two new complexes, namely bis{1‐[(benzotriazol‐1‐yl)methyl]‐1H‐1,3‐imidazole‐κN 3}dibromidomercury(II), [HgBr2(C10H9N5)2], and bis{1‐[(benzotriazol‐1‐yl)methyl]‐1H‐1,3‐imidazole‐κN 3}diiodidomercury(II), [HgI2(C10H9N5)2], have been synthesized through the self‐assembly of bmi with HgBr2 or HgI2. Single‐crystal X‐ray diffraction shows that both complexes are mononuclear structures, in which the bmi ligands coordinate to the HgII ions in monodentate modes. In the solid state, both complexes display three‐dimensional networks formed by a combination of hydrogen bonds and π–π interactions. The IR spectra and PXRD patterns of both complexes have also been recorded. 相似文献
4.
Treatment of (NH4)[Au(D‐Hpen‐S)2](D‐H2pen = D‐penicillamine) with CoCl2·6H2O in an acetate buffer solution, followed by air oxidation, gave neutral AuICoIII and anionic AuI3CoIII2 polynuclear complexes, [Au3Co3(D‐pen‐N,O,S)6]([ 1 ]) and [Au3Co2(D‐pen‐N,S)6]3? ([ 2 ]3?), which were separated by anion‐exchange column chromatography. Complexes [ 1 ] and [ 2 ]3? each formed a single isomer, and their structures were determined by single‐crystal X‐ray crystallography. In [ 1 ], each of three [Au(D‐pen‐S)2]3?metalloligands coordinates to two CoIII ions in a bis‐tridentate‐N,O,S mode to form a cyclic AuI3CoIII3 hexanuclear structure, in which three [Co(D‐pen‐N,O,S)2]? octahedral units and six bridging S atoms adopt trans(O) geometrical and R chiral configurations, respectively. In [ 2 ]3?, each of three [Au(D‐pen‐S)2]3? metalloligands coordinates to two CoIII ions in a bis‐bidentate‐N,S mode to form a AuI3CoIII2 pentanuclear structure, in which two [Co(D‐pen‐N,S)3]3? units and six bridging S atoms adopt ∧ and R chiral configurations, respectively. 相似文献
5.
Synthesis,Characterization, and Photoluminescence Properties of Silver(I) Metal‐Organic Polymers with Nanochannels Based on 2‐Sulfoterephthalic Acid and Di(pyridin‐2‐yl)amine Ligands 下载免费PDF全文
Hui Huang Mahmood Payehghadr Jie Wang Hong‐Ping Xiao Ai‐Yin Wang Xin‐Hua Li Ali Morsali 《Helvetica chimica acta》2014,97(3):345-354
Two new silver(I) 3D coordination polymers, namely [Ag3(2‐stp)(dpa)]n ( 1 ) and {[Ag2(2‐stp)(H2O)]?Hdpa}n ( 2 ) (2‐NaH2stp=sodium 2,5‐dicarboxysulfonate, dpa=di(pyridine‐2‐yl)amine) were synthesized. The complexes were characterized by elemental analysis, FT‐IR spectra, thermogravimetric analyses (TGA), and single‐crystal X‐ray diffraction. In complex 1 , three neighboring Ag ions are bridged by N‐ and O‐atom, forming a 3D coordination network. The molecular structure of 2 is cation? anion species, forming 3D host? guest supramolecular network with the [Hdpa]+ cations encapsulated in the nanochannels. The photoluminescence properties of the complexes were also investigated in the solid state at room temperature. 相似文献
6.
Synthesis,structural and chemosensitivity studies of arene d6 metal complexes having N‐phenyl‐N´‐(pyridyl/pyrimidyl)thiourea derivatives 下载免费PDF全文
Sanjay Adhikari Omar Hussain Roger M. Phillips Werner Kaminsky Mohan Rao Kollipara 《应用有机金属化学》2018,32(6)
The d6 metal complexes of thiourea derivatives were synthesized to investigate its cytotoxicity. Treatment of various N‐phenyl‐N´ pyridyl/pyrimidyl thiourea ligands with half‐sandwich d6 metal precursors yielded a series of cationic complexes. Reactions of ligand (L1‐L3) with [(p‐cymene)RuCl2]2 and [Cp*MCl2]2 (M = Rh/Ir) led to the formation of a series of cationic complexes bearing general formula [(arene)M(L1)к2(N,S)Cl]+, [(arene)M(L2)к2(N,S)Cl]+ and [(arene)M(L3)к2(N,S)Cl]+ [arene = p‐cymene, M = Ru ( 1 , 4 , 7 ); Cp*, M = Rh ( 2 , 5 , 8 ); Cp*, Ir ( 3 , 6 , 9 )]. These compounds were isolated as their chloride salts. X‐ray crystallographic studies of the complexes revealed the coordination of the ligands to the metal in a bidentate chelating N,S‐ manner. Further the cytotoxicity studies of the thiourea derivatives and its complexes evaluated against HCT‐116 (human colorectal cancer), MIA‐PaCa‐2 (human pancreatic cancer) and ARPE‐19 (non‐cancer retinal epithelium) cancer cell lines showed that the thiourea ligands displayed no activity. Upon complexation however, the metal compounds possesses cytotoxicity and whilst potency is less than cisplatin, several complexes exhibited greater selectivity for HCT‐116 or MIA‐PaCa‐2 cells compared to ARPE‐19 cells than cisplatin in vitro. Rhodium complexes of thiourea derivatives were found to be more potent as compared to ruthenium and iridium complexes. 相似文献
7.
Elena Bermejo Alfonso Castieiras Ricardo Domínguez Rosa Carballo Ccilia Maichle‐Mssmer Joachim Strhle Douglas X. West 《无机化学与普通化学杂志》1999,625(6):961-968
Reaction of group 12 metal dihalides in ethanolic media with 2‐acetylpyridine 4N‐phenylthiosemicarbazone ( H4PL ) and 2‐acetylpyridine‐N‐oxide 4N‐phenylthiosemicarbazone ( H4PLO ) afforded the compounds [M(H4PL)X2] (X = Cl, Br, M = Zn, Cd, Hg; X = I, M = Zn, Cd) ( 1–8 ), [Hg(4PL)I]2 ( 9 ) and [M(H4PLO)X2] (X = Cl, Br, I, M = Zn, Cd, Hg) ( 10–18 ). H4PL , H4PLO and their complexes were characterized by elemental analysis and by IR and 1H and 13C NMR spectroscopy (and the cadmium complexes by 113Cd NMR spectroscopy), and H4PL , H4PLO , ( 5 · DMSO) and ( 9 ) were additionally studied by X‐ray diffraction. H4PL is N,N,S‐tridentate in all its complexes, including 9 , in which it is deprotonated, and H4PLO is in all cases O,N,S‐tridentate. In all the complexes, the metal atoms are pentacoordinate and the coordination polyhedra are redistorted tetragonal pyramids. In assays of antifungal activity against Aspergillus niger and Paecilomyces variotii, the only compound to show any activity was [Hg(H4PLO)I2] ( 18 ). 相似文献
8.
Synthesis and Structural Characterization of a Novel Heterodinuclear Vanadium(IV)‐Nickel(II) Complex
A novel VIV‐NiII heterodinuclear complex [VO(cat)2][Ni(1, 2‐PDA)2H2O] ( 1 ) (cat = catechol; 1, 2‐PDA = 1, 2‐propane diamine) was synthesized at low temperature (10 °C) and characterized by IR spectroscopy and X‐ray diffraction. A novel Ni–O=V structure exists in the complex, the vanadyl–catechol moiety and the nickel–diamine moiety are connected by an oxygen bridge; all molecules are further assembled into crystallites by O–H ··· O hydrogen bonds. 相似文献
9.
Assembly,Structures, and Properties of a Series of Metal‐Organic Coordination Polymers Derived from a Semi‐rigid Bis‐pyridyl‐bis‐amide Ligand 下载免费PDF全文
Xiu‐Li Wang Xiao‐Ting Sha Guo‐Cheng Liu Nai‐Li Chen Chun‐Hua Gong Yun Qu 《无机化学与普通化学杂志》2015,641(7):1274-1281
Four metal‐organic coordination polymers [Cd(4‐bpcb)1.5Cl2(H2O)] ( 1 ), [Cd(4‐bpcb)0.5(mip)(H2O)2] · 3H2O ( 2 ), [Co(4‐bpcb)(oba)(H2O)2] ( 3 ), and [Ni(4‐bpcb)(oba)(H2O)2] ( 4 ) [4‐bpcb = N,N′‐bis(4‐pyridinecarboxamide)‐1, 4‐benzene, H2mip = 5‐methylisophthalic acid, and H2oba = 4, 4′‐oxybis(benzoic acid)] were synthesized under hydrothermal conditions and characterized by single‐crystal X‐ray diffraction, elemental analyses, IR spectroscopy, powder X‐ray diffraction, and TG analysis. In complex 1 , two Cl– anions serve as bridges to connect two Cd‐(μ1‐4‐bpcb) subunits forming a dinuclear unit, which are further linked by μ2‐bridging 4‐bpcb to generate 1D zigzag chain. Complex 2 shows a 2D 63 network constructed by [Cd‐mip]n zigzag chains and μ2‐bridging 4‐bpcb ligands. Complexes 3 and 4 are isostructural 2D (4, 4) grid networks derived from [M‐oba]n (M = Co, Ni) zigzag chains and [M‐(4‐bpcb)]n linear chains. The 1D chains for 1 and the 2D networks for 2 – 4 are finally extended into 3D supramolecular architectures by hydrogen bonding interactions. The roles of dicarboxylates and central metal ions on the assembly and structures of the target compounds were discussed. Moreover, the thermal stabilities, photoluminescent properties, and photocatalytic activities of complexes 1 – 4 and the electrochemical properties of complexes 3 and 4 were investigated. 相似文献
10.
ReV‐Phthalocyaninates and ReV‐Tetraphenylporphyrinates: Synthesis, Properties, and Crystal Structure Hexa‐coordinated ReV phthalocyaninates (pc) and ReV tetraphenylporphyrinates (tpp) of the type [Re(O)(X)p] (p: pc, tpp) with X = OCH3, ReO4, Cl/pc, F/pc, OH/tpp, [{Re(O)p}2(μ‐O)] and (cat)trans[Re(O)2p] (cat: nBu4N, Et4N/tpp) have been isolated and characterised by their UV‐Vis‐NIR, IR and resonance Raman (RR) spectra. In the RR spectra, the intensity of the (Re=O) and (Re–X) stretching vibrations (ν(Re=O/–X)) in [Re(O)(X)p] and [{Re(O)p}2(μ‐O)] is selectively enhanced with excitation in coincidence with O → Re–CT between ca 19000 and 22000 cm–1. In accordance to selection rules, data of ν(Re=O/–X) compare well with those of the complementary IR spectra. Because of the trans influence ν(Re=O) depends on the axial ligand X, ranging from 940 to 1010 cm–1. The crystallographic characterization of [Re(O)(ReO4)tpp] · CHCl3 ( 1 ), [{Re(O)tpp}2(μ‐O)] · py ( 2 ), (nBu4N)trans[Re(O)2tpp] ( 3 ), and (Et4N)trans[Re(O)2tpp] · 2 H2O ( 4 ) is described. The tpp centered Re atom is in a distorted octahedron of four N atoms of the porphyrinate and two axial O atoms in a mutual trans position. Average Re–N distances are 2.062 Å in 1 , 2.086 Å in 2 , 2.089 Å in 3 , and 2.082/2.086 Å in 4 . The Re–O distance of the terminal rhenyl group varies from 1.64(1) Å ( 1 ), 1.73(1)/1.70(1) Å ( 2 ) to 1.80(1) Å ( 4 ), that of the monodentate rhenate(VII) from 1.70(1) to 1.75(1) Å. The Re–O distances in the bridge of the linear O=Re–O–Re=O skeleton in 2 are 1.95(1)/1.89(1) Å. In 1 , with a bent O=Re–O^ ReO3 moiety (∢(Re–O^ReO3) = 143(1)°) and a mostly ionic coordinated rhenate(VII), these distances differ significantly (2.20(1) Å vs 1.75(1) Å). The porphyrinate in 1 is saucer‐shaped with a distal rhenate(VII), and the tpp centered Re atom is displaced by 0.31 Å out of the (N)4 plane towards the rhenyl‐O atom. The distorted porphyrinates in 2 are rotated by 30.4(4)°, and the Re atoms are 0.1 Å out of their (N)4 planes towards the terminal O atoms. In 3 and 4 the porphyrinates are almost planar with the Re atom in their centre. 相似文献
11.
Three coordination polymers, namely [Co(BDC)( L )] · H2O ( 1 ), [Co(NPH)( L )] · H2O ( 2 ), and [Ni(NPH)( L )(H2O)3] · H2O ( 3 ) [H2BDC = 1, 3‐benzenedicarboxylic acid, H2NPH = 3‐nitrophthalic acid, L = N,N′‐bis(3‐pyridyl)‐terephthalamide] were hydrothermally synthesized by self‐assembly of cobalt/nickel chloride with a semi‐rigid bis‐pyridyl‐bis‐amide ligand and two aromatic dicarboxylic acids. Single crystal X‐ray diffraction analyses revealed that complexes 1 and 2 are two‐dimensional (2D) coordination polymers containing a one‐dimensional (1D) ribbon‐like Co‐dicarboxylate chain and a 1D zigzag Co‐ L chain. Although the coordination numbers of CoII ions and the coordination modes of two dicarboxylates are different in complexes 1 and 2 , they have a similar 3, 5‐connected {42.67.8}{42.6} topology. In complex 3 , the adjacent NiII ions are linked by L ligands to form a 1D polymeric chain, whereas the 1D chains does not extend into a higher‐dimensional structure due to the ligand NPH with monodentate coordination mode. The adjacent layers of complexes 1 and 2 and the adjacent chains of 3 are further linked by hydrogen bonding interactions to form 3D supramolecular networks. Moreover, the thermal stabilities, fluorescent properties, and photocatalytic activities of complexes 1 – 3 were studied. 相似文献
12.
Two mixed‐metal‐center inorganic‐organic hybrid frameworks incorporating N‐(Phosphonomethyl)iminodiacetate(H4pmida), [Zn2V2O2(pmida)2(H2O)10]·H2O ( 1 ) and [Zn2V2O2(pmida)2(H2O)12]·2H2O ( 2 ), were synthesized by hydrothermal reactions and characterized by elemental analysis, IR spectra, UV‐Vis spectra and single crystal X‐ray analysis. In complex 1 , the centrosymmetric dimeric [V2O2(pmida)2]4– unit connected to neighboring Zn2+ through the phosphonate group, while 2 the [V2O2(pmida)2]4– unit uncoordinated with the Zn2+ in the presence of NaOH. Magnetic measurements in the range 2‐300 K have shown weak antiferromagnetic interaction between the adjacent vanadium ions in complexes. 相似文献
13.
Novel isolated,L‐amino acid‐ligated rhodium catalysts that induce highly helix‐sense‐selective polymerization of an achiral 3,4,5‐trisubstituted phenylacetylene 下载免费PDF全文
Hongge Jia Yongqiang Shi Liqun Ma Xuan Gao Yazhen Wang Yu Zang Jijun Peng Toshiki Aoki Masahiro Teraguchi Takashi Kaneko Toshio Masuda 《Journal of polymer science. Part A, Polymer chemistry》2016,54(15):2346-2351
Two novel chiral well‐defined rhodium complexes, Rh(cod)(L‐Phe) (cod = 1,5‐cyclooctadiene, Phe = phenylalanine) and Rh(cod)(L‐Val) (Val = valine) were synthesized, isolated by recrystallization, and characterized. The helix‐sense‐selective polymerization (HSSP) of an achiral 3,4,5‐trisubstituted phenylacetylene, p‐dodecyloxy‐m,m‐dihydroxyphenylacetylene (DoDHPA) was examined by using the two Rh complexes as catalysts. These catalysts provided high molecular weight polymers (Mw 28 × 104?45 × 104) in about 40%–85% yields. The resulting polymers exhibited a bisignated CD signal at about 300 nm and a broad signal around 470 nm, indicating that they have preferential one‐handed helical structure. The present catalysts achieved larger molar ellipticity up to [θ]310 = 13.0 × 104 deg cm2/dmol than those with binary chiral catalytic systems, [Rh(cod)Cl]2/(L‐phenylalaninol), [Rh(cod)Cl]2/(L‐valinol), and [Rh(nbd)Cl]2/(R)‐PEA. All these results manifest that the present, well‐defined Rh complexes serve as excellent catalysts for the HSSP of DoDHPA. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2346–2351 相似文献
14.
Ma. Angeles Pelez Teresa Ramírez Marcos Martínez Pankaj Sharma Cecilio lvarez Ren Gutirrez 《无机化学与普通化学杂志》2004,630(10):1489-1494
The enantiopure ketoimine of benzil – the ( S )‐(‐)‐(1‐phenylethylimino)benzyl phenyl ketone ( 1 ) obtained under microwave irradiation in solvent‐free conditions – reacts with Na2[PdCl4] to give the new chiral mono‐ and dinuclear Pd‐complexes 2 and 3 , which have been partly characterized by IR, 1H and 13C NMR spectroscopies along with MS‐FAB+ spectrometry. The crystal and molecular structures of both complexes has been fully confirmed by single‐crystal X‐ray studies. On the other hand, investigations in vitro of 2 and 3 have displayed growth inhibition against different classes of cancer: leukemia (K‐562 CML), colon cancer (HCT‐15), cancer breast (MCF‐7), central nervous system (U‐251 Glio) and prostate cancer (PC‐3) cell lines. 相似文献
15.
The synthesis and characterization of aluminum alkoxide and alkyl complexes stabilized by piperazidine‐bridged bis(phenolate) ligands are described. Treatment of ligand precursors H2[ONNO]1 {H2[ONNO]1=1,4‐bis(2‐hydroxy‐3‐tert‐butyl‐5‐methylbenzyl)piperazidine} and H2[ONNO]2 {H2[ONNO]2=1,4‐bis(2‐hydroxy‐3,5‐di‐tert‐butylbenzyl)piperazidine} with AlEt2(OCH2Ph) and AlEt2(OPr‐i), which were generated in situ by the reactions of AlEt3 with equivalent of the corresponding alcohols, in a 1:1 molar ratio in THF gave the corresponding aluminum alkoxide complexes [ONNO]1Al(OCH2Ph) ( 1 ) and [ONNO]2Al(OPr‐i) ( 2 ), respectively. The reaction of H2[ONNO]1 with AlEt2(OCH2Ph) in a 1:2 molar ratio in THF afforded a mixture of monometallic aluminum ethyl complex [ONNO]1AlEt ( 3 ) and complex 1 , which can be isolated by stepwise crystallization. Similarly, H2[ONNO]2 reacted with AlEt2(OPr‐i) in a 1:2 molar ratio in THF to give a mixture of aluminum ethyl complex [ONNO]2AlEt ( 4 ) and complex 2 . Complexes 1 and 2 were also available via treatment of complexes 3 and 4 with 1 equiv. of benzyl alcohol and isopropyl alcohol, respectively. All of these complexes were fully characterized including X‐ray structural determination. It was found that complexes 1 to 4 can initiate the ring‐opening polymerization of ε‐caprolactone, and complexes 1 and 2 showed higher catalytic activity in comparison with complexes 3 and 4 . 相似文献
16.
合成了两个新的配合物CuLCl2•2EtOH(1) 和CoLCl2 (2) [L是( S , S )-1,2-二N-甲基苯并咪唑-1,2-二甲氧基-乙烷],并通过单晶X衍射确定它们的结构。配合物1中,L作为三齿[N, N, O]配体,而配合物2 中,L作为二齿[N, N]配体。这两个配合物共同的结构特点都是通过分子内氢键形成2维的格子结构,然后通过分子间的C-H···Cl型氢键和π–π堆积作用形成3维结构。 相似文献
17.
Feng Gao Hui Chao Feng Zhou Lian‐Cai Xu Kang‐Cheng Zheng Liang‐Nian Ji 《Helvetica chimica acta》2007,90(1):36-51
Two novel chiral ruthenium(II) complexes, Δ‐[Ru(bpy)2(dmppd)]2+ and Λ‐[Ru(bpy)2(dmppd)]2+ (dmppd = 10,12‐dimethylpteridino[6,7‐f] [1,10]phenanthroline‐11,13(10H,12H)‐dione, bpy = 2,2′‐bipyridine), were synthesized and characterized by elemental analysis, 1H‐NMR and ES‐MS. The DNA‐binding behaviors of both complexes were studied by UV/VIS absorption titration, competitive binding experiments, viscosity measurements, thermal DNA denaturation, and circular‐dichroism spectra. The results indicate that both chiral complexes bind to calf‐thymus DNA in an intercalative mode, and the Δ enantiomer shows larger DNA affinity than the Λ enantiomer does. Theoretical‐calculation studies for the DNA‐binding behaviors of these complexes were carried out by the density‐functional‐theory method. The mechanism involved in the regulating and controlling of the DNA‐binding abilities of the complexes was further explored by the comparative studies of [Ru(bpy)2(dmppd)]2+ and of its parent complex [Ru(bpy)2(ppd)]2+ (ppd = pteridino[6,7‐f] [1,10]phenanthroline‐11,13 (10H,12H)‐dione). 相似文献
18.
《应用有机金属化学》2017,31(8)
A set of vanadium(III) complexes, namely {SNO}VCl2(THF)2 ( 2a , SNO = thiophene‐(N═CH)‐phenol; 2b , SNO = 5‐phenylthiophene‐(N═CH)‐phenol; 2c , SNO = 5‐phenylthiophene‐(N═CH)‐4‐tert ‐butylphenol; 2d , SNO = 5‐methylthiophene‐(N═CH)‐phenol; 2e , SNO = 5‐methylthiophene‐(N═CH)‐4‐tert ‐butylphenol; 2f , SNO = 5‐methylthiophene‐(N═CH)‐2‐methylphenol; 2g , SNO = 5‐methylthiophene‐(N═CH)‐4‐fluorophenol), were synthesized by reaction of VCl3(THF)3 with phenoxy–imine–thiophene proligands ( 1a – g ). All vanadium(III) complexes were characterized using elemental analysis and infrared and electron paramagnetic resonance spectroscopies. Upon activation with methylaluminoxane (MAO), vanadium precatalysts 2a – g proved active in the polymerization of ethylene (213.6–887.2 kg polyethylene (mol[V])−1⋅h−1), yielding high‐density polyethylenes with melting temperatures in the range 133–136 °C and crystallinities varying from 28 to 41%. The 2e/ MAO catalyst system was able to copolymerize ethylene with 1‐hexene affording poly(ethylene‐co ‐1‐hexene)s with melting temperatures varying from 126 to 102 °C and co‐monomer incorporation in the range 3.60–4.00%. 相似文献
19.
《应用有机金属化学》2017,31(11)
The reaction of [Pd(CH3CN)2Cl2] with N ‐functional group‐substituted 2‐iminomethylpyrrole‐based ligands, namely N 1‐((1H‐pyrrol‐2‐yl)methylene)‐N 3,N 3‐dimethylpropane‐1,3‐diamine (LA), N 1‐((1H‐pyrrol‐2‐yl)methylene)‐N 3‐methyl‐N 3‐phenylpropane‐1,3‐diamine (LB), N ‐((1H‐pyrrol‐2‐yl)methylene)‐3‐(methylthio)propan‐1‐amine (LC) and N ‐((1H‐pyrrol‐2‐yl)methylene)‐3‐methoxypropan‐1‐amine (LD), resulted in [Ln PdCl] (Ln = LA–LD) complexes in high yield via N─H bond activation of pyrrole moiety without use of base. [Ln PdCl] existed as monomeric four‐coordinated complexes with slightly distorted square planar geometries around the palladium metal center. The ligands show N ,N ′,X ‐tridentate binding mode to the palladium metal center to give two fused ring metallacycles. [LBPdCl] gave the highest activity (3.29 × 105 g PMMA (mol Pd)−1 h−1) for a methyl methacrylate (MMA) polymerization in the presence of modified methylaluminoxane at 60 °C compared to the other Pd(II) analogues, and resulted in PMMA with higher molecular weight (M w = 7.16 × 105 g mol−1) and narrower polydispersity index. Syndiotactic‐enriched PMMA resulted in all cases. 相似文献
20.
Antonio Carlos Niedwieski Jaísa Fernandes Soares George Jeffery Leigh Fbio Souza Nunes Joaquim Delphino Da Motta Neto 《International journal of quantum chemistry》2002,88(2):245-251
This work is concerned with prospective starting materials for the synthesis of larger molecules used as functional models of the substrate binding and reducing site of the vanadium nitrogenase. It is well known that the mononuclear adduct of vanadium(II) chloride with N,N,N′,N′‐tetramethylethylenediamine, henceforth referred to as [VCl2(tmeda)2], is a good starting material for the synthesis of trinuclear vanadium complexes. We now report the results of semiempirical calculations on the spectroscopy of [VCl2(tmeda)2] using the intermediate neglect of differential overlap (INDO) method. For the mononuclear complex, the ground state was calculated to be a quartet, about 45 kcal/mol below the doublet. For the positively charged trinuclear vanadium complex, [V3(μ‐Cl)3(μ3‐Cl)2(tmeda)3]+, the ground state was calculated to be a decatet, about 47 kcal/mol below the octet. For both complexes the frontier orbitals are dominated by the vanadium 3d manifold, and accordingly the electronic spectra are dominated by d‐d* excitations within this manifold. The INDO/S‐calculated spectra are in good agreement with the observed UV‐visible spectra in both cases. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem 88: 245–251, 2002 相似文献