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1.
《Magnetic resonance in chemistry : MRC》2002,40(2):153-156
Variable‐temperature 1H and 77Se NMR data for 3‐phenylselenenyl‐1‐phenyl‐1‐propene (1) in the presence of Rh2(MTPA)4 (Rh*) prove that the equilibria are strongly shifted towards the adduct Rh*···1; free selenide molecules cannot be detected as long as uncomplexed rhodium atoms are available. In the case of excess Rh*, both 1 : 2 and 1 : 1 adducts (Rh* vs 1) are formed, and the latter is slightly favoured. With excess selenide, the system strongly favours the complexation of two selenide molecules (1 : 2 adduct), i.e. one at each rhodium atom. In this situation, intermolecular selenide exchange can be monitored by variable‐temperature 1H NMR spectroscopy and the energy barrier is estimated to be 54–55 kJ mol?1. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
2.
A novel method for the preparation of chromogenic calixarenes with azo groups was reported.p-Substituted(-NO2,-CH3,-Cl)amilines were diazotized with isoamyl nitrite in EtONa/EtOH under refluxing condition.Fifteen mono-,bis-,tris-and tetrakis(p-substituted phenyl)azo calix[4]arenes (including proximal and distal isomers) were obtainged respectively by diazo-coupling in different molar ratio to calix[4]arenes(1) under pH=7.5-9.0 in non-aqueous solution at 0-5℃.^1H NMR and ^13C NMR spectra of (p-substtituted phenyl)azo calix[4]-arenes indicated that they existed in cone conformation in solution. 相似文献
3.
The title compound has been prepared from [Ti(η5‐C5Me5)Cl3] and cis‐cis‐(t‐BuSi(OH)—CH2)3 in hexane solution in the presence of Et3N. The pale yellow complex was characterized by NMR and MS spectra, as well as by a crystal structure determination. The two crystallographic independent molecules in the triclinic unit cell (space group P1¯, No. 2, Z = 4) both have a nearly identical adamantane‐like TiO3Si3C3 cage of approximate C3v symmetry. The exocyclic C—C—C bond angles in the Cp‐ligand range from 123° to 129°. A quantum chemical calculation of the free molecule predicts this range to be 124° to 127°. The arrangement of the molecules in the crystal is characteristic for an offset face‐to‐face ππ stacking of the aromatic η5‐C5Me5 rings. 相似文献
4.
Lilianna Chciska Lesaw Siero Maria Bukowska‐Strzyewska Zbigniew H. Kudzin Lszl Fbin 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(1):o46-o50
The structures of diphenyl [3‐methyl‐1‐(3‐phenylthioureido)butyl]phosphonate and diphenyl [2‐methyl‐1‐(3‐phenylthioureido)butyl]phosphonate, both C24H27N2O3PS, are reported. In both compounds, the thiourea moiety adopts a syn–syn conformation (i.e. the S—C—N—C torsion angles are synperiplanar), which enables N—H⋯O hydrogen bonds to be formed between centrosymmetrically related molecules. The geometries around the P atoms can be described as distorted tetrahedral. Some of the functional groups in each structure are disordered. The bulk of the different alkyl substituents between the amide and phosphonate groups influences the molecular conformation and crystal packing. Although the structures of these compounds and two related derivatives appear to be similar, they are not isostructural. 相似文献
5.
Andrzej Domaski Krzysztof Ejsmont Janusz B. Kyzio Jacek Zaleski 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):467-470
Two isomeric trans‐4‐aminoazoxybenzenes, trans‐1‐(4‐aminophenyl)‐2‐phenyldiazene 2‐oxide (α, C12H11N3O) and trans‐2‐(4‐aminophenyl)‐1‐phenyldiazene 2‐oxide (β, C12H11N3O), have been characterized by X‐ray diffraction. The α isomer is almost planar, having torsion angles along the Caryl—N bonds of only 4.9 (2) and 8.0 (2)°. The relatively short Caryl—N bond to the non‐oxidized site of the azoxy group [1.401 (2) Å], together with the significant quinoid deformation of the respective phenyl ring, is evidence of conjugation between the aromatic sextet and the π‐electron system of the azoxy group. The geometry of the β isomer is different. The non‐substituted phenyl ring is twisted with respect to the NNO plane by ca 50°, whereas the substituted ring is almost coplanar with the NNO plane. The non‐oxidized N atom in the β isomer has increased sp3 character, which leads to a decrease in the N—N—C bond angle to 116.8 (2)°, in contrast with 120.9 (1)° for the α isomer. The deformation of the C—C—C angles (1–2°) in the phenyl rings at the substitution positions is evidence of the different character of the oxidized and non‐oxidized N atoms of the azoxy group. In the crystal structures, molecules of both isomers are arranged in chains connected by weak N—H?O (α and β) and N—H?N (β) hydrogen bonds. 相似文献
6.
《Magnetic resonance in chemistry : MRC》2003,41(9):703-708
Detailed solution‐NMR studies on the distorted ruthenium hydride complex [RuH(η6‐toluene)(Binap)](CF3SO3) (2) are reported. NOE‐spectroscopy, together with low‐temperature 1H and 31P NMR data, reveals restricted rotation around a P—C bond for a specific axial P—phenyl ring with the activation energy determined via simulation. From 19F, 1H HOESY data, the approach of the triflate anion relative to the hydride ligand is established. Comparison of the quadrupole coupling constant CQF from both solution‐ and solid‐state MAS‐NMR on the deuteride [RuD(η6‐benzene)(Binap)](CF3SO3) (1‐D) provide information on the nature of the Ru—H bond. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
7.
Choudhury M. Zakaria George Ferguson Alan J. Lough Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(4):o204-o208
The adduct 1,6‐diaminohexane–1,1,1‐tris(4‐hydroxyphenyl)ethane (1/2) is a salt {hexane‐1,6‐diyldiammonium–4‐[1,1‐bis(4‐hydroxyphenyl)ethyl]phenolate (1/2)}, C6H18N22+·2C20H17O3?, in which the cation lies across a centre of inversion in space group P. The anions are linked by two short O—H?O hydrogen bonds [H?O 1.74 and 1.76 Å, O?O 2.5702 (12) and 2.5855 (12) Å, and O—H?O 168 and 169°] into a chain containing two types of R(24) ring. Each cation is linked to four different anion chains by three N—H?O hydrogen bonds [H?O 1.76–2.06 Å, N?O 2.6749 (14)–2.9159 (14) Å and N—H?O 156–172°]. In the adduct 2,2′‐bipyridyl–1,1,1‐tris(4‐hydroxyphenyl)ethane (1/2), C10H8N2·2C20H18O3, the neutral diamine lies across a centre of inversion in space group P21/n. The tris(phenol) molecules are linked by two O—H?O hydrogen bonds [H?O both 1.90 Å, O?O 2.7303 (14) and 2.7415 (15) Å, and O—H?O 173 and 176°] into sheets built from R(38) rings. Pairs of tris(phenol) sheets are linked via the diamine by means of a single O—H?N hydrogen bond [H?N 1.97 Å, O?N 2.7833 (16) Å and O—H?N 163°]. 相似文献
8.
Choudhury M. Zakaria George Ferguson Alan J. Lough Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):o1-o5
In the adduct 1,2‐bis(4‐pyridyl)ethane–1,1,1‐tris(4‐hydroxyphenyl)ethane (1/2), C12H12N2·2C20H18O3, the bipyridyl component lies across an inversion centre in P. The tris‐phenol molecules [systematic name: 4,4′,4′′‐(ethane‐1,1,1‐triyl)triphenol] are linked by O—H?O hydrogen bonds to form sheets built from R(38) rings, and symmetry‐related pairs of sheets are linked by the bipyridyl molecules via O—H?N hydrogen bonds to form open bilayers. Each bilayer is interwoven with two adjacent bilayers, forming a continuous three‐dimensional structure. In the adduct 1,2‐bis(4‐pyridyl)ethene–1,1,1‐tris(4‐hydroxyphenyl)ethane–methanol (1/1/1), C12H10N2·C20H18O3·CH4O, the molecules are linked by O—H?O and O—H?N hydrogen bonds into three interwoven three‐dimensional frameworks, generated by single spiral chains along [010] and [001] and a triple‐helical spiral along [100]. 相似文献
9.
Bi‐Yun Su Jia‐Xiang Wang Xiang Liu Qian‐Ding Li 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(8):851-854
In the title compound, [Ni(C12H11N2)2], the NiII cation lies on an inversion centre and has a square‐planar coordination geometry. This transition metal complex is composed of two deprotonated N,N′‐bidentate 2‐[(phenylimino)ethyl]‐1H‐pyrrol‐1‐ide ligands around a central NiII cation, with the pyrrolide rings and imine groups lying trans to each other. The Ni—N bond lengths range from 1.894 (3) to 1.939 (2) Å and the bite angle is 83.13 (11)°. The Ni—N(pyrrolide) bond is substantially shorter than the Ni—N(imino) bond. The planes of the phenyl rings make a dihedral angle of 78.79 (9)° with respect to the central NiN4 plane. The molecules are linked into simple chains by an intermolecular C—H...π interaction involving a phenyl β‐C atom as donor. Intramolecular C—H...π interactions are also present. 相似文献
10.
Pavel E. Kazin Andrey S. Karpov Martin Jansen Jürgen Nuss Yury D. Tretyakov 《无机化学与普通化学杂志》2003,629(2):344-352
Strontium phosphate apatites containing different amounts of copper were prepared by a solid state reaction at 1100 °C or by arc melting above 1600 °C in air. The samples were characterized by X‐ray diffraction, ICP analysis, scanning electron microscopy, IR spectroscopy, MAS—1H—NMR, diffuse reflectance spectroscopy, and SQUID magnetometry. X‐ray crystal structure determination was carried out for a single crystal obtained from the melt. The compound is formulated as Sr5(PO4)3(CuO2)1/3 and has an apatite structure (space group P63/m, a = 9.7815(4)Å, c = 7.3018(4)Å, Z = 2) with linear CuO23— ions occupying hexagonal channels. For solid state synthesized samples, Rietveld refinement of powder XRD patterns was performed. The samples obtained at 1100 °C acquire the composition Sr5(PO4)3CuxOHy, with x changing from 0.01 to 0.62 and y < 1—x. The copper content can be increased to x = 0.85 by annealing in argon at 950 °C. The compounds represent a hydroxyapatite in which part of the protons is substituted by Cu+ and Cu2+ ions. The ions form linear O—Cu—O units which are progressively condensed creating the Cu—O—Cu bridges on increasing copper content. IR and NMR data testify existence of OH groups, non‐disturbed and disturbed by neighboring Cu atoms. In the electron spectra, the samples exhibit absorption bands at 7800‐7900, 14200‐14500 and 17500‐17550 cm—1, which were assigned to Cu2+ d‐electron transitions. By annealing the sample with x = 0.1 in oxygen at 800 °C copper is fully oxidized while retaining in channels in unusual for Cu2+ linear coordination. 相似文献
11.
A new kind of soluble structure‐ordered ladder‐like polysilsesquioxane with reactive side‐chain 2‐(4‐chloromethyl phenyl) ethyl groups ( L ) was first synthesized by stepwise coupling polymerization. The monomer, 2‐(4‐chloromethyl phenyl) ethyltrichlorosilane ( M ), was synthesized successfully by hydrosilylation reaction with dicyclopentadienylplatinum(II) chloride (Cp2PtCl2) catalyst. Monomer and polymer structures were characterized by FT‐IR, 1H‐NMR, 13C‐NMR, 29Si‐NMR, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), vapor pressure osmometry (VPO) and X‐ray diffraction (XRD). This novel reactive ladder‐like polymer has promise potential applications as initiator for atom transfer radical polymerization, and as precursor for a variety of advanced functional polymers. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
12.
Qi‐Wei Lu Thomas R. Hoye Christopher W. Macosko 《Journal of polymer science. Part A, Polymer chemistry》2002,40(14):2310-2328
Two model urethane compounds, dibutyl 4,4′‐methylenebis(phenyl carbamate) (BMB) and dioctyl 4,4′‐methylenebis(phenyl carbamate) (OMO) were prepared by capping 4,4′‐methylenebis(phenyl isocyanate) with n‐butanol and n‐octanol, respectively. The reactions of the two model urethane compounds with several small monofunctional compounds as well as two model poly(ethylene glycols) were carried out with neat mixtures at elevated temperatures. The ranking of reactivity of the functional groups with the urethanes was determined as follows—primary amine > secondary amine ? hydroxyl ~ acid ~ anhydride ? epoxide. Nuclear magnetic resonance spectroscopy (NMR) was used for the quantitative analysis. Fourier transform infrared spectroscopy was used to complement the NMR analysis. Conversions of carbamate in each reaction were monitored over time at constant temperature (200 °C). The reactions between OMO and primary amine were conducted at 170, 180, 190, and 200 °C and best described with a second‐order bimolecular reaction model. The rate constant was estimated to be 1.8 × 10?3 L · mol?1 · s?1 and activation energy 115 kJ · mol?1. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2310–2328, 2002 相似文献
13.
Mahalingam Vanjinathan A. Raghavan A. Sultan Nasar 《Journal of polymer science. Part A, Polymer chemistry》2007,45(14):2959-2977
3,5‐bis(4‐aminophenoxy)phenyl phenylcarbamate—a novel AB2‐type blocked isocyanate monomer and 3,5‐bis{ethyleneoxy(4‐aminophenoxy)}phenyl carbonyl azide—a novel AB2‐type azide monomer were synthesized in high yield. Step‐growth polymerization of these monomers were found to give a first example of hyperbranched poly (aryl‐ether‐urea) and poly(aryl‐alkyl‐ether‐urea). Molecular weights (Mw) of the polymer were found to vary from 1,858 to 52,432 depending upon the monomer and experimental conditions used. The polydispersity indexes were relatively narrow due to the controlled regeneration of isocyanate functional groups for the polymerization reaction. The degree of branching (DB) was determined using 1H‐NMR spectroscopy and the values ranged from 87 to 54%. All the polymers underwent two‐stage decomposition and were stable up to 300 °C. Functionalized end‐capping of poly(aryl‐ether‐urea) using phenylchloroformate and di‐t‐butyl dicarbonate (Boc)2O changed the thermal properties and solubility of the polymers. Copolymerization of AB2‐type blocked isocyante monomer with functionally similar AB monomer were also carried out. The molecular weights of copolymers were found to be in the order of 6 × 105 with narrow dispersity. It was found that the Tg's of poly(aryl‐alkyl‐ether‐urea)s were significantly less (46–49 °C) compared to poly(aryl‐ether‐urea)s. Moreover the former showed melting transition at 154 °C, which was not observed in the latter case. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2959–2977, 2007 相似文献
14.
A. Moghimi Sh. Sheshmani A. Shokrollahi H. Aghabozorg M. Shamsipur G. Kickelbick M. Carla Aragoni V. Lippolis 《无机化学与普通化学杂志》2004,630(4):617-624
A novel 1:2 proton transfer self‐associated compound LH2 , (GH+)2(pydc2—), was synthesized from the reaction of dipicolinic acid, pydcH2, (2, 6‐pyridinedicarboxylic acid), and guanidine hydrochloride, (GH+)(Cl—). The characterization was performed using IR, 1H and 13C NMR spectroscopy and single‐crystal X‐ray diffraction. LH2 · H2O crystallizes in the space group C2/c of the monoclinic system and contains eight molecules per unit cell. The unit cell dimensions are: a = 26.480(5)Å, b = 8.055(2)Å, c = 14.068(3)Å. The first coordination complex (GH)2[Cd(pydc)2] · 2H2O, was prepared using LH2 and cadmium(II) iodide, and characterized by 1H and 13C NMR spectroscopy and X‐ray crystallography. The crystal system is triclinic with space group P1¯ with one molecule per unit cell. The unit cell dimensions are: a = 8.5125(7)Å, b = 11.0731(8)Å, c = 13.2404(10)Å. The cadmium(II) atom is six‐coordinated with a distorted octahedral geometry. The two pydc2— units are almost perpendicular to each other. The protonation constants of the building blocks of the pydc‐guanidine adduct, the equilibrium constants for the reaction of pydc2— with guanidine and the stoichiometry and stability of the Cd2+ complex with LH2 in aqueous solution were accomplished by potentiometric pH titration. The solution studies strongly support a self‐association between pydc2— and GH+ with a stoichiometry for the CdII complex similar to that observed for the isolated crystalline complex. In fact, the [Cd(pydc)2]2— complex was found as the most abundant species in solution (> 90 %) at a pH >5. 相似文献
15.
Jia Wang Tianchao You Teng Wang Qikui Liu Jianping Ma Guoxia Jin 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(6):806-811
The adsorption behaviour of the CdII–MOF {[Cd(L)2(ClO4)2]·H2O ( 1 ), where L is 4‐amino‐3,5‐bis[3‐(pyridin‐4‐yl)phenyl]‐1,2,4‐triazole, for butan‐2‐one was investigated in a single‐crystal‐to‐single‐crystal (SCSC) fashion. A new host–guest system that encapsulated butan‐2‐one molecules, namely poly[[bis{μ3‐4‐amino‐3,5‐bis[3‐(pyridin‐4‐yl)phenyl]‐1,2,4‐triazole}cadmium(II)] bis(perchlorate) butanone sesquisolvate], {[Cd(C24H18N6)2](ClO4)2·1.5C4H8O}n, denoted C4H8O@Cd‐MOF ( 2 ), was obtained via an SCSC transformation. MOF 2 crystallizes in the tetragonal space group P43212. The specific binding sites for butan‐2‐one in the host were determined by single‐crystal X‐ray diffraction studies. N—H…O and C—H…O hydrogen‐bonding interactions and C—H…π interactions between the framework, ClO4? anions and guest molecules co‐operatively bind 1.5 butan‐2‐one molecules within the channels. The adsorption behaviour was further evidenced by 1H NMR, IR, TGA and powder X‐ray diffraction experiments, which are consistent with the single‐crystal X‐ray analysis. A 1H NMR experiment demonstrates that the supramolecular interactions between the framework, ClO4? anions and guest molecules in MOF 2 lead to a high butan‐2‐one uptake in the channel. 相似文献
16.
Jose G. Trujillo‐Ferrara Efrn V. García‐Bez Itzia I. Padilla‐Martínez Francisco J. Martínez‐Martínez Norberto Farfan‐García 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o427-o430
In exo‐2‐(3,5‐dioxo‐10‐oxa‐4‐azatricyclo[5.2.1.02,6]dec‐8‐en‐4‐yl)phenyl acetate, C16H13NO5, the plane of the acetoxy group lies almost perpendicular to that of the phenyl ring [dihedral angle = 89.8 (1)°], in contrast with the smaller deviations found in the para isomer exo‐4‐(3,5‐dioxo‐10‐oxa‐4‐azatricyclo[5.2.1.02,6]dec‐8‐en‐4‐yl)phenyl acetate, C16H13NO5, these being 63.6 (1) and 37.0 (1)° for the two crystallographically independent molecules. Irrespective of the position of the acetoxy group, both compounds pack through soft C—H⋯X (X is O or phenyl) interactions, forming interlinked centrosymmetric tetramers in the bc plane. 相似文献
17.
Vinicius Oliveira Araujo Brbara Tirloni Lívia Streit Vnia Denise Schwade 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(1):1-7
Semicarbazones can exist in two tautomeric forms. In the solid state, they are found in the keto form. This work presents the synthesis, structures and spectroscopic characterization (IR and NMR spectroscopy) of four such compounds, namely the neutral molecule 4‐phenyl‐1‐[phenyl(pyridin‐2‐yl)methylidene]semicarbazide, C19H16N4O, (I), abbreviated as HBzPyS, and three different hydrated salts, namely the chloride dihydrate, C19H17N4O+·Cl?·2H2O, (II), the nitrate dihydrate, C19H17N4O+·NO3?·2H2O, (III), and the thiocyanate 2.5‐hydrate, C19H17N4O+·SCN?·2.5H2O, (IV), of 2‐[phenyl({[(phenylcarbamoyl)amino]imino})methyl]pyridinium, abbreviated as [H2BzPyS]+·X?·nH2O, with X = Cl? and n = 2 for (II), X = NO3? and n = 2 for (III), and X = SCN? and n = 2.5 for (IV), showing the influence of the anionic form in the intermolecular interactions. Water molecules and counter‐ions (chloride or nitrate) are involved in the formation of a two‐dimensional arrangement by the establishment of hydrogen bonds with the N—H groups of the cation, stabilizing the E isomers in the solid state. The neutral HBzPyS molecule crystallized as the E isomer due to the existence of weak π–π interactions between pairs of molecules. The calculated IR spectrum of the hydrated [H2BzPyS]+ cation is in good agreement with the experimental results. 相似文献
18.
Ronald Callahan Orlando Ramirez Kerstin Rosmarion Robert Rothchild Kevin C. Bynum 《Journal of heterocyclic chemistry》2005,42(5):889-898
A series of hindered Diels‐Alder adducts have been prepared from phencyclone, 1 , with various unusual symmetrical cyclic dienophiles, including cyclohexene, 2a ; vinylene carbonate, 2b ; vinylene trithiocarbonate, 2c ; and the N‐aryl maleimides: N‐(4‐dimethylamino‐3,5‐dinitrophenyl)maleimide (“Tuppy's maleimide”), 2d ; and N‐[3,5‐bis(trifluoromethyl)phenyl]maleimide, 2e . The highly hindered adducts, 3a‐e , respectively, were extensively characterized by one‐ and two‐dimensional NMR methods, observing proton, carbon‐13 and fluorine‐19. High resolution COSY45 spectra permitted rigorous proton NMR assignments. The 2D heteronuclear C‐H chemical shift correlation spectra (HETCOR, XHCORR) were obtained for adducts 3a‐d , allowing specific assignments for protonated carbons. Corrections to earlier proton NMR assignments for the vinylene carbonate adduct are given; results of the gated decoupling 13C NMR experiment for this adduct supported endo adduct stereochemistry. Relative proton chemical shifts for bridgehead phenyls of adduct 3c appeared anomalous relative to other adducts, suggesting possible special anisotropic interactions (with endocyclic sulfur or other anisotropic groups in the product) due to the unusual calculated orientation of the phenyls. The unsubstituted bridgehead phenyls in all adducts were shown to exhibit slow exchange limit (SEL) 1H and 13C spectra on the NMR timescales at ambient temperatures (7 tesla) showing slow rotations about the C(sp3)‐C(aryl sp2) bonds. The rapid rotation of the N‐aryl rings of the maleimide adducts was indicated by fast exchange limit spectra, suggesting that ortho substitution of the N‐aryl ring may be necessary to slow this rotation to the SEL regime. Ab initio geometry optimizations at the Hartree‐Fock level were carried out for each adduct, with the 6‐31G* basis sets. Appreciable geometry differences were seen in calculated structures, and significant NMR chemical shift differences were experimentally observed, depending on the nature of the groups attached to the (Z)‐HC=CH moiety of the dienophiles. 相似文献
19.
Abolghasem Moghimi Shabnam Sheshmani Ardeshir Shokrollahi Mojtaba Shamsipur Guido Kickelbick Hossein Aghabozorg 《无机化学与普通化学杂志》2005,631(1):160-169
The proton transfer compound LH2 , (phenH+)2(pydc2—), has been prepared from 1, 10‐phenanthroline, phen, and 2, 6‐pyridinedicarboxylic acid, (dipicolinic acid), pydcH2. Characterization was performed using solution and solid phase CP/MAS 13C NMR and IR spectroscopy. The reactions of this adduct with ZnSO4·7H2O and Zn(NO3)2·4H2O give the complexes, [Zn(pydc)2][Zn(phen)2(H2O)2]·7H2O (1) and [Zn(phen)3]4(H(Hpydc)2)(NO3)7·26H2O (2) , respectively. These complexes were characterized by 1H and 13C NMR spectroscopy and single crystal X‐ray analysis. The complexes crystallize in the triclinic space group P1 with Z = 2. The unit cell dimensions for complex 1 and 2 are: a = 9.9838(9) Å, b = 14.7483(13) Å, c = 14.8365(13) Å and a = 12.640(4) Å, b = 15.855(5) Å, c = 21.830(7) Å, respectively. In complex 1 (pydc2—) and phen, are tri‐ and bidentate ligands, respectively, and an anionic [Zn(pydc)2]2— and cationic [Zn(phen)2(H2O)2]2+ complex are formed simultaneously. In complex 2 , three phen participate in complexation leaving hydrogen‐bis(pyridine‐2‐carboxylate), (H(Hpydc)2)— as a supramolecular anion. The fragments (H(Hpydc)2)—, 7 NO3—, and 26 H2O in complex 2 are joined together by extensive and strong H‐bonding; therefore, the structure is composed of [Zn(phen)3]48+, and an anionic hydrogen bond supramolecular assembly with the formula, {(H(Hpydc)2(NO3)7)8— · 26H2O}n. The anionic species (H(Hpydc)2)— has a special position at the inversion center, as well as one of the NO3— anions, which is disordered over the inversion center. Most of the hydrogen bonds in complex 2 represent strong H‐bonding. The protonation constants of the building blocks of the pydc‐phen adduct, the equilibrium constants for the reaction of (pydc2—) with phenanthroline and the stoichiometry and stability of the ZnII complex with LH2 on aqueous solution were determined by potentiometric pH titration. The solution study results support self‐association between (pydc2—) and (phenH+) with a stoichiometry for the Zn(II) complex similar to that observed for the isolated crystalline complex. 相似文献
20.
Sergio A. Moya Juana Gajardo Juan C. Araya Jaime J. Cornejo Véronique Guerchais Hubert Le Bozec J. Carles Bayón Alvaro J. Pardey Pedro Aguirre 《应用有机金属化学》2008,22(8):471-478
Novel ruthenium (II) complexes were prepared containing 2‐phenyl‐1,8‐naphthyridine derivatives. The coordination modes of these ligands were modified by addition of coordinating solvents such as water into the ethanolic reaction media. Under these conditions 1,8‐naphthyridine (napy) moieties act as monodentade ligands forming unusual [Ru(CO)2Cl2(η1‐2‐phenyl‐1,8‐naphthyridine‐ kN )(η1‐2‐phenyl‐1,8‐naphthyridine‐kN′)] complexes. The reaction was reproducible when different 2‐phenyl‐1,8‐naphthyridine derivatives were used. On the other hand, when dry ethanol was used as the solvent we obtained complexes with napy moieties acting as a chelating ligand. The structures proposed for these complexes were supported by NMR spectra, and the presence of two ligands in the [Ru(CO)2Cl2(η1‐2‐phenyl‐1,8‐naphthyridine‐ kN )(η1‐2‐phenyl‐1,8‐naphthyridine‐kN′)] type complexes was confirmed using elemental analysis. All complexes were tested as catalysts in the hydroformylation of styrene showing moderate activity in N,N′‐dimethylformamide. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献