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1.
《Supramolecular Science》1997,4(1-2):51-58
The Dawson-type anion [X(n)2M18O62]2(8 − n)−, is derived from the Keggin anion [X(n)M12O40](8 −n)− (X=Si, Ge, P, S) by fusing two trivalant shells, producing an oval shaped closed framework. The central oxoanions, contributing an overall charge to the clathratic cluster, retain tetrahedral coordination. Generally, the Dawson heteropolyoxometalates are more thermally stable and catalytically more active than the corresponding Keggin ions. In this work, the comparisons among the Keggin and Dawson ions are addressed in terms of relative stability, hardness and acidity. These predictions are based on the theoretical results obtained from the extended Hückel, EH calculations. This analysis of the Dawson structure presently represents the most significant modelling work on large oxyanions. Absolute comparisons between the EH and density functional are not available for Dawson structures. The correlations between these methods have been shown valid for the Keggin ions and are expected to be similar for the Dawson ions. The substitution chemistry of the central oxoanions is similar to that of the Keggin clusters in both the stability and acidity. 相似文献
2.
A Keggin Polyoxometalate Shows Water Oxidation Activity at Neutral pH: POM@ZIF‐8, an Efficient and Robust Electrocatalyst
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Subhabrata Mukhopadhyay Dr. Joyashish Debgupta Chandani Singh Aranya Kar Prof. Samar K. Das 《Angewandte Chemie (International ed. in English)》2018,57(7):1918-1923
Keggin‐type polyoxometalate anions [XM12O40]n? are versatile, as their applications in interdisciplinary areas show. The Keggin anion [CoW12O40]6? turns into an efficient and robust electrocatalyst upon its confinement in the well‐defined void space of ZIF‐8, a metal–organic framework (MOF). [H6CoW12O40]@ZIF‐8 is so stable to water oxidation that it retains its initial activity even after 1000 catalytic cycles. The catalyst has a turnover frequency (TOF) of 10.8 mol O2(mol Co)?1 s?1, one of the highest TOFs for electrocatalytic oxygen evolution at neutral pH. Controlled experiments rule out the chances of formation and participation of CoOx in this electrocatalyic water oxidation. 相似文献
3.
Satoshi Matsunaga Yusuke Inoue Takuya Otaki Hironori Osada Kenji Nomiya 《无机化学与普通化学杂志》2016,642(7):539-545
Al‐ and Ga‐containing open‐Dawson polyoxometalates (POMs), K10[{Al4(μ‐OH)6}{α,α‐Si2W18O66}] · 28.5H2O ( Al4 ‐ open ) and K10[{Ga4(μ‐OH)6}(α,α‐Si2W18O66)] · 25H2O ( Ga4 ‐ open ) were synthesized by the reaction of trilacunary Keggin POM, [A‐α‐SiW9O34]10–, with Al(NO3)3 · 9H2O or Ga(NO3)3 · nH2O, and unequivocally characterized by single‐crystal X‐ray analysis, 29Si and 183W NMR, and FT‐IR spectroscopy as well as elemental analysis and TG/DTA. Single‐crystal X‐ray analysis revealed that the {M4(μ‐OH)6}6+ (M = Al, Ga) clusters were included in an open pocket of the open‐Dawson polyanion, [α,α‐Si2W18O66]16–, which was constituted by the fusion of two trilacunary Keggin POMs via two W–O–W bonds. These two open‐Dawson structural POMs showed clear difference of the bite angles depending on the size of ionic radii. In cases of both compounds, the solution 29Si and 183W NMR spectra in D2O showed only one signal and five signals, respectively. These spectra were consistent with the molecular structures of Al4 ‐ and Ga4 ‐ open , suggesting that these polyoxoanions were obtained as single species and maintained their molecular structures in solution. 相似文献
4.
Malika Ammam Bineta Keita Louis Nadjo Israel‐Martyr Mbomekalle Michelle D. Ritorto Travis M. Anderson Wade A. Neiwert Craig L. Hill Jan Fransaer 《Electroanalysis》2011,23(6):1427-1434
The electrochemical behavior of two manganese (Mn)‐substituted polyoxoanions, the dissymmetrical Dawson sandwich‐type [MnII4(H2O)2(H4AsW15O56)2]18? and the Keggin sandwich banana‐shaped [((MnIIOH2)MnII2PW9O34)2(PW6O26)]17? is investigated. At pH 5, the oxidation of the MnII‐centers results in one oxidation wave for [MnII4(H2O)2(H4AsW15O56)2]18? and two oxidation waves for [((MnIIOH2)MnII2PW9O34)2(PW6O26)]17?. To the best of our knowledge, presence of the second Mn‐based wave is rarely observed in the electrochemistry of Mn‐containing polyoxometalates. Deposition of Mn‐oxides electrocatalysts for dioxygen reduction is noticed by cyclic voltammetry, which can be distinguished by the significant positive shift in potentials of the dioxygen reduction reaction. 相似文献
5.
Koji Tanaka 《Chemical record (New York, N.Y.)》2009,9(3):169-186
Proton dissociation of an aqua‐Ru‐quinone complex, [Ru(trpy)(q)(OH2)]2+ (trpy = 2,2′ : 6′,2″‐terpyridine, q = 3,5‐di‐t‐butylquinone) proceeded in two steps (pKa = 5.5 and ca. 10.5). The first step simply produced [Ru(trpy)(q)(OH)]+, while the second one gave an unusual oxyl radical complex, [Ru(trpy)(sq)(O?.)]0 (sq = 3,5‐di‐t‐butylsemiquinone), owing to an intramolecular electron transfer from the resultant O2? to q. A dinuclear Ru complex bridged by an anthracene framework, [Ru2(btpyan)(q)2(OH)2]2+ (btpyan = 1,8‐bis(2,2′‐terpyridyl)anthracene), was prepared to place two Ru(trpy)(q)(OH) groups at a close distance. Deprotonation of the two hydroxy protons of [Ru2(btpyan)(q)2(OH)2]2+ generated two oxyl radical Ru‐O?. groups, which worked as a precursor for O2 evolution in the oxidation of water. The [Ru2(btpyan)(q)2(OH)2](SbF6)2 modified ITO electrode effectively catalyzed four‐electron oxidation of water to evolve O2 (TON = 33500) under electrolysis at +1.70 V in H2O (pH 4.0). Various physical measurements and DFT calculations indicated that a radical coupling between two Ru(sq)(O?.) groups forms a (cat)Ru‐O‐O‐Ru(sq) (cat = 3,5‐di‐t‐butylcathechol) framework with a μ‐superoxo bond. Successive removal of four electrons from the cat, sq, and superoxo groups of [Ru2(btpyan)(cat)(sq)(μ‐O2?)]0 assisted with an attack of two water (or OH?) to Ru centers, which causes smooth O2 evolution with regeneration of [Ru2(btpyan)(q)2(OH)2]2+. Deprotonation of an Ru‐quinone‐ammonia complex also gave the corresponding Ru‐semiquinone‐aminyl radical. The oxidized form of the latter showed a high catalytic activity towards the oxidation of methanol in the presence of base. Three complexes, [Ru(bpy)2(CO)2]2+, [Ru(bpy)2(CO)(C(O)OH)]+, and [Ru(bpy)2(CO)(CO2)]0 exist as an equilibrium mixture in water. Treatment of [Ru(bpy)2(CO)2]2+ with BH4? gave [Ru(bpy)2(CO)(C(O)H)]+, [Ru(bpy)2(CO)(CH2OH)]+, and [Ru(bpy)2(CO)(OH2)]2+ with generation of CH3OH in aqueous conditions. Based on these results, a reasonable catalytic pathway from CO2 to CH3OH in electro‐ and photochemical CO2 reduction is proposed. A new pbn (pbn = 2‐pyridylbenzo[b]‐1,5‐naphthyridine) ligand was designed as a renewable hydride donor for the six‐electron reduction of CO2. A series of [Ru(bpy)3‐n(pbn)n]2+ (n = 1, 2, 3) complexes undergoes photochemical two‐ (n = 1), four‐ (n = 2), and six‐electron reductions (n = 3) under irradiation of visible light in the presence of N(CH2CH2OH)3. © 2009 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 9: 169–186; 2009: Published online in Wiley InterScience ( www.interscience.wiley.com ) DOI 10.1002/tcr.200800039 相似文献
6.
Prof. Dr. Meilin Wei Xiaoxiang Wang Dr. Xianying Duan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(5):1607-1616
We have succeeded in constructing a metal–organic framework (MOF), [Cu(bpdc)(H2O)2]n (H2bpdc=2,2′‐bipyridyl‐3,3′‐dicarboxylic acid, 1 ), and two poly‐POM–MOFs (POM=polyoxometalate), {H[Cu(Hbpdc)(H2O)2]2[PM12O40] ? n H2O}n (M=Mo for 2 , W for 3 ), by the controllable self‐assembly of H2bpdc, Keggin‐anions, and Cu2+ ions based on electrostatic and coordination interactions. Notably, these three compounds all crystallized in the monoclinic space group P21/n, and the Hbpdc? and bpdc2? ions have the same coordination mode. Interestingly, in compounds 2 and 3 , Hbpdc? and the Keggin‐anion are covalently linked to the transition metal copper at the same time as polydentate organic ligand and as polydentate inorganic ligand, respectively. Complexes 2 and 3 represent new and rare examples of introducing the metal N‐heterocyclic multi‐carboxylic acid frameworks into POMs, thereby, opening a pathway for the design and the synthesis of multifunctional hybrid materials based on two building units. The Keggin‐anions being immobilized as part of the metal N‐heterocyclic multi‐carboxylic acid frameworks not only enhance the thermal stability of compounds 2 and 3 , but also introduce functionality inside their structures, thereby, realizing four approaches in the 1D hydrophilic channel used to engender proton conductivity in MOFs for the first time. Complexes 2 and 3 exhibit good proton conductivity (10?4 to ca. 10?3 S cm?1) at 100 °C in the relative humidity range 35 to about 98 %. 相似文献
7.
Olga M. Nazarenko Eduard B. Rusanov Alexander N. Chernega Konstantin V. Domasevitch 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(3):232-236
In poly[[bis(μ‐4,4′‐bi‐1H‐pyrazole‐κ2N2:N2′)bis(3‐carboxyadamantane‐1‐carboxylato‐κO1)cobalt(II)] dihydrate], {[Co(C12H15O4)2(C6H6N4)2]·2H2O}n, (I), the Co2+ cation lies on an inversion centre and the 4,4′‐bipyrazole (4,4′‐bpz) ligands are also situated across centres of inversion. In its non‐isomorphous cadmium analogue, {[Cd(C12H15O4)2(C6H6N4)2]·2H2O}n, (II), the Cd2+ cation lies on a twofold axis. In both compounds, the metal cations adopt an octahedral coordination, with four pyrazole N atoms in the equatorial plane [Co—N = 2.156 (2) and 2.162 (2) Å; Cd—N = 2.298 (2) and 2.321 (2) Å] and two axial carboxylate O atoms [Co—O = 2.1547 (18) Å and Cd—O = 2.347 (2) Å]. In both structures, interligand hydrogen bonding [N...O = 2.682 (3)–2.819 (3) Å] is essential for stabilization of the MN4O2 environment with its unusually high (for bulky adamantanecarboxylates) number of coordinated N‐donor co‐ligands. The compounds adopt two‐dimensional coordination connectivities and exist as square‐grid [M(4,4′‐bpz)2]n networks accommodating monodentate carboxylate ligands. The interlayer linkage is provided by hydrogen bonds from the carboxylic acid groups via the solvent water molecules [O...O = 2.565 (3) and 2.616 (3) Å] to the carboxylate groups in the next layer [O...O = 2.717 (3)–2.841 (3) Å], thereby extending the structures in the third dimension. 相似文献
8.
Following the Reaction of Heteroanions inside a {W18O56} Polyoxometalate Nanocage by NMR Spectroscopy and Mass Spectrometry
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Qi Zheng Dr. Laia Vilà‐Nadal Dr. Christoph Busche Dr. Jennifer S. Mathieson Dr. De‐Liang Long Prof. Dr. Leroy Cronin 《Angewandte Chemie (International ed. in English)》2015,54(27):7895-7899
By incorporating phosphorus(III)‐based anions into a polyoxometalate cage, a new type of tungsten‐based unconventional Dawson‐like cluster, [W18O56(HPIIIO3)2(H2O)2]8?, was isolated, in which the reaction of the two phosphite anions [HPO3]2? within the {W18O56} cage could be followed spectroscopically. As well as full X‐ray crystallographic analysis, we studied the reactivity of the cluster using both solution‐state NMR spectroscopy and mass spectrometry. These techniques show that the cluster undergoes a structural rearrangement in solution whereby the {HPO3} moieties dimerize to form a weakly interacting (O3PH???HPO3) moiety. In the crystalline state the cluster exhibits a thermally triggered oxidation of the two PIII template moieties to form PV centers (phosphite to phosphate), commensurate with the transformation of the cage into a Wells–Dawson {W18O54} cluster. 相似文献
9.
Co‐Adsorption of O2 and CO on Au2−: Infrared Photodissociation Spectroscopy and Theoretical Study of [Au2O2(CO)n]− (n=2–6)
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Hao Liu Prof. Xiaopeng Xing Prof. Xuefeng Wang Hui Qu Prof. Guan‐jun Wang Prof. Ming‐fei Zhou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(6):2085-2091
The co‐adsorption of O2 and CO on anionic sites of gold species is considered as a crucial step in the catalytic CO oxidation on gold catalysts. In this regard, the [Au2O2(CO)n]? (n=2–6) complexes were prepared by using a laser vaporization supersonic ion source and were studied by using infrared photodissociation spectroscopy in the gas phase. All the [Au2O2(CO)n]? (n=2–6) complexes were characterized to have a core structure involving one CO and one O2 molecule co‐adsorbed on Au2? with the other CO molecules physically tagged around. The CO stretching frequency of the [Au2O2(CO)]? core ion is observed around =2032–2042 cm?1, which is about 200 cm?1 higher than that in [Au2(CO)2]?. This frequency difference and the analyses based on density functional calculations provide direct evidence for the synergy effect of the chemically adsorbed O2 and CO. The low lying structures with carbonate group were not observed experimentally because of high formation barriers. The structures and the stability (i.e., the inertness in a sense) of the co‐adsorbed O2 and CO on Au2? may have relevance to the elementary reaction steps on real gold catalysts. 相似文献
10.
Jun Ying Xiao‐Ling Lin Yu‐Jing Liu Ru Xiao Xiu‐Li Wang Dr. Ai‐Xiang Tian 《无机化学与普通化学杂志》2012,638(9):1351-1355
Two new Keggin templated supramolecular compounds, [Zn2(H2biim)5(SiM12O40)] · 4H2O [M = W ( 1 ), Mo ( 2 )] (H2biim = 2, 2′‐biimidazole), were synthesized under hydrothermal conditions by using the ligand 2, 2′‐biimidazole. They were characterized by single‐crystal X‐ray diffraction, elemental analyses, IR and photoluminescence spectroscopy as well as cyclic voltammetry. The two isostructural compounds are constructed by two discrete supramolecular moieties: the inorganic chains consist of Keggin anions and metal‐organic chains constructed by [Zn2(H2biim)5]4+ subunits. In the dinuclear [Zn2(H2biim)5]4+ subunit, the H2biim ligands exhibit a dual role, chelating and linking. The metal‐organic chains further construct a 3D supramolecular framework with channels, in which the Keggin‐based inorganic chains are accommodated. The electrochemical behaviors of compounds 1 and 2 bulk‐modified carbon paste electrodes ( 1 ‐CPE, 2 ‐CPE) were studied. 相似文献
11.
A mono‐cobalt substituted Wells–Dawson polyoxometalate with an antenna ligand linked to the CoII atom, was prepared by reaction of the mono‐vacant Wells–Dawson precursor [P2W17O61]10– with a imidazole‐cobalt complex by using the bench method. It was isolated as the imidazole salt: (HIm)7H[P2W17O61Co(Im)] · 4H2O ( 1 ) (Im = imidazole). Compound 1 was characterized by elemental analysis, IR and UV/Vis spectroscopy, TG analysis, cyclic voltammetry and single‐crystal/powder X‐ray diffraction. This is the first example of the 3d transition metal mono‐substituted Wells–Dawson polyoxometalate with an antenna ligand. 相似文献
12.
Werner Complexes with ω‐Dimethylaminoalkyl Substituted Ethylenediamine Ligands: Bifunctional Hydrogen‐Bond‐Donor Catalysts for Highly Enantioselective Michael Additions
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M. Sc. Subrata K. Ghosh Dr. Carola Ganzmann Dr. Nattamai Bhuvanesh Prof. Dr. John A. Gladysz 《Angewandte Chemie (International ed. in English)》2016,55(13):4356-4360
The racemic carbonate complex [Co(en)2O2CO]+ Cl? (en=1,2‐ethylenediamine) and (S)‐[H3NCH((CH2)nNHMe2)CH2NH3]3+ 3 Cl? (n=1–4) react (water, charcoal, 100 °C) to give [Co(en)2((S)‐H2NCH((CH2)nNHMe2)CH2NH2)]4+ 4 Cl? ( 3 a – d H4+ 4 Cl?) as a mixture of Λ/Δ diastereomers that separate on chiral‐phase Sephadex columns. These are treated with NaOH/Na+ BArf? (BArf=B(3,5‐C6H3(CF3)2)4) to give lipophilic Λ‐ and Δ‐ 3 a–d 3+ 3 BArf?, which are screened as catalysts (10 mol %) for additions of dialkyl malonates to nitroalkenes. Optimal results are obtained with Λ‐ 3 c 3+ 3 BArf? (CH2Cl2, ?35 °C; 98–82 % yields and 99–93 % ee for six β‐arylnitroethenes). The monofunctional catalysts Λ‐ and Δ‐[Co(en)3]3+ 3 BArf? give enantioselectivities of <10 % ee with equal loadings of Et3N. The crystal structure of Δ‐ 3 a H4+ 4 Cl? provides a starting point for speculation regarding transition‐state assemblies. 相似文献
13.
Cation Effect on Formation of Preyssler‐type 30‐Tungsto‐5‐phosphate: Enhanced Yield of Na‐encapsulated Derivative and Direct Synthesis of Ca‐ and Bi‐Encapsulated Derivatives
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Akio Hayashi Terufumi Haioka Keita Takahashi Bassem S. Bassil Ulrich Kortz Tsuneji Sano Masahiro Sadakane 《无机化学与普通化学杂志》2015,641(15):2670-2676
The effect of cations in a reaction mixture for the preparation of the Preyssler‐Jeannin‐Pope type 30‐tungsto‐5‐phosphate [P5W30O110Na]14– is investigated. Reaction of phosphate and tungstate with a P/W ratio of ca. 3.9 in an acidic aqueous solution without cations selectively leads to the Dawson‐type 18‐tungsto‐2‐phosphate, [P2W18O62]6–. Amongst all the alkali cations, only Na+ allows formation of the Preyssler‐type polyanion [P5W30O110Na]14–, with an encapsulated Na+ ion, and the product yield can be improved by increasing Na+ amount. The presence of Li+ ions instead results in the Dawson‐type polyanion [P2W18O62]6–, whereas K+, Rb+, and Cs+ selectively result in the Keggin‐type polyanion [PW12O40]3–. An improved synthetic procedure for the Na+‐encapsulated Preyssler‐ion leading to a higher isolated yield is presented. Furthermore, addition of Ca2+ and Bi3+ compounds allows formation of the Ca2+‐ and Bi3+‐encapsulated Preyssler‐type polyanions, [P5W30O110Ca]13– and [P5W30O110Bi]12–, respectively. Furthermore, single‐crystal XRD structure of the Bi3+‐encapsulated Preyssler‐type polyanions, [P5W30O110Bi]12–, is presented for the first time. 相似文献
14.
Polynuclear Pd(II) and Ni(II) complexes of macrocyclic polyamine 3,6,9,16,19,22‐hexaazatricyclo[22.2.2.211,14]‐triaconta 11,13,24,26(l),27,29‐hexaene (L) in solution were investigated by electrospray ionization mass spectrometry (ESIMS). For methanol solution of complexes M2LX4 (M = Pd(II) and Ni(II), X= Cl and I), two main clusters of peaks were observed which can be assigned to [M2LX3]+ and [M2LX2]2+. When Pd2LCl4 was treated with 2 or 4 mol of AgNO3, it gave rise formation of Pd2LCl2 (NO3)2 · H2O and [Pd2L(H2O)m(NO3)n](4‐n)+, respectively. ESMS spectra show that the dissociation of the former in the ionization process gave peaks of [Pd2LCl2]2+ and [(Pd2LCl2)NO3]+, while dissociation of the later gave the peaks of [Pd2L(CH3CO2)2]2+ and [Pd2L(CH3CO2)2](NO3) + in the presence of acetic acid. Similar species were observed for Pd2LI4 when treated with 4 mol of AgNO3. When [Pd2L · (H2O)m(NO3)n](4‐n)+ reacted with 2 mol of oxalate anions at 40°C, [Pd4L2(C2O4)2(NO3)2]2+ and [Pd4L2(C2O4)2 (NO3)]3+ were detected. This implies the formation of square‐planar molecular box Pd4L2(C2O4)2(NO3)4 in which C2O4? may act as bridging ligands as confirmed by crystal structure analysis. The dissociation form and the stability of complex cations in gaseous state are also discussed. This work provides an excellent example of the usefulness of ESIMS in the identification of metal complexes in solution. 相似文献
15.
A 3D Polyoxometalate‐Based Framework Constructed from Ag/trz Metal‐Organic Ribbons and P2W18 Polyoxoanions: Synthesis,Structure and Electrochemical Properties
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A Wells‐Dawson Polyoxometalate‐based hybrid, Ag9(trz)3(Htrz)4 (H2O)(P2W18O62)·3H2O ( 1 ) (Htrz = 1,2,4‐1H‐triazole) was hydrothermally synthesized through using trz ligand and silver nitrate in the presence of [P2W18O62]6– polyoxoanion. In the 3D framework structure of compound 1 , two kinds of wave‐like Ag/trz chains originated from trz ligands and silver cations are aggregated in a “2+1” mode by {Ag2/trz} linkages to result in a 1D Ag/trz metal‐organic ribbon, which is further extended into a 3D framework structure by [P2W18O62]6– polyoxoanions through Ag‐O covalent bonds. Additionally, the electrochemical properties of compound 1 have also been investigated. 相似文献
16.
《Journal of Coordination Chemistry》2012,65(19):3363-3371
Two new banana-shaped tungstophosphates [M6(H2O)2(PW9O34)2(PW6O26)]17 ? (MII?=?NiII, CoII) incorporating two types of lacunary polyoxometalate units have been synthesized in aqueous solution and characterized by elemental analyses, IR, and UV spectra, and single-crystal X-ray diffraction. Structural analyses show that Na6H11[Ni6(H2O)2(PW9O34)2(PW6O26)]?·?32H2O (1) and Na7H10[Co6(H2O)2(PW9O34)2(PW6O26)]?· 31H2O (2) are generated from two tri-MII substituted B-α-[(MOH2)M2PW9O34] Keggin units connected by a hexavacant [PW6O26]11? Keggin fragment, leading to the MII-containing banana-shaped tungstophosphates. Magnetic properties of 2 show decrease of the molar magnetic susceptibility at higher temperatures results from spin-orbit coupling of CoII and antiferromagnetic interactions whereas the maximum at the lower temperatures is indicative of the ferromagnetic interactions within the trinuclear CoII spin cluster in the sandwich belt. 相似文献
17.
Duyen N. K. Pham Mrittika Roy Ava Kreider-Mueller James A. Golen David R. Manke 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(5):568-574
Seven crystal structures of five first‐row (Fe, Co, Ni, Cu, and Zn) and one second‐row (Cd) transition metal–4‐picoline (pic)–sulfate complexes of the form [M(pic)x]SO4 are reported. These complexes are catena‐poly[[tetrakis(4‐methylpyridine‐κN)metal(II)]‐μ‐sulfato‐κ2O:O′], [M(SO4)(C6H7N)4]n, where the metal/M is iron, cobalt, nickel, and cadmium, di‐μ‐sulfato‐κ4O:O‐bis[tris(4‐methylpyridine‐κN)copper(II)], [Cu2(SO4)2(C6H7N)6], catena‐poly[[bis(4‐methylpyridine‐κN)zinc(II)]‐μ‐sulfato‐κ2O:O′], [Zn(SO4)(C6H7N)2]n, and catena‐poly[[tris(4‐methylpyridine‐κN)zinc(II)]‐μ‐sulfato‐κ2O:O′], [Zn(SO4)(C6H7N)3]n. The Fe, Co, Ni, and Cd compounds are isomorphous, displaying polymeric crystal structures with infinite chains of MII ions adopting an octahedral N4O2 coordination environment that involves four picoline ligands and two bridging sulfate anions. The Cu compound features a dimeric crystal structure, with the CuII ions possessing square‐pyramidal N3O2 coordination environments that contain three picoline ligands and two bridging sulfate anions. Zinc crystallizes in two forms, one exhibiting a polymeric crystal structure with infinite chains of ZnII ions adopting a tetrahedral N2O2 coordination containing two picoline ligands and two bridging sulfate anions, and the other exhibiting a polymeric crystal structure with infinite chains of ZnII ions adopting a trigonal bipyramidal N3O2 coordination containing three picoline ligands and two bridging sulfate anions. The structures are compared with the analogous pyridine complexes, and the observed coordination environments are examined in relation to crystal field theory. 相似文献
18.
Doris Freiesleben Thomas Hauck Karlheinz Sünkel Wolfgang Beck Prof. Dr. 《无机化学与普通化学杂志》2007,633(7):1100-1106
Metal Complexes of Biologically Important Ligands. CLXVI Metal Complexes with Ferrocenylmethylcysteinate and 1,1′‐Ferrocenylbis‐(methylcysteinate) as Ligands A series of complexes of transition metal ions ( Cr3+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+ ) and of lanthanide ions ( La3+, Nd3+, Gd3+, Dy3+, Lu3+ ) with the anions of ferrocenylmethyl‐L‐cysteine [(C5H5)Fe(C5H4CH(R)SCH2CH(NH3+)CO2?] (L1) and with the dianions of 1,1′‐ferrocenylbis(methyl‐L‐cysteine) [Fe(C5H4CH(R)SCH2CH(NH3+) CO2?)2] (R = H, Me, Ph) (L2) as N,O,S‐donors were prepared. With the monocysteine ferrocene derivative L1 as ligands complexes [MIIL12] or [CrIIIL12]Cl type complexes are formed whereas the bis(cysteine) ligand L2 yields insoluble complexes of type [ML2]n, presumably as coordination polymers. The magnetic moments of [MnIIL2]n, [PrIIIL2]n(OH)n and [DyIIIL2]n(OH)n exhibit “normal” paramagnetism. 相似文献
19.
Jovica Stojanovi Tamara ?or?evi Ljiljana Karanovi 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(11):i91-i94
During an investigation of the insufficiently known system M1O–M2O–X2O5–H2O (M1 = Cd2+, Sr2+ and Ba2+; M2 = Cu2+, Ni2+, Co2+, Zn2+ and Mg2+; X = P5+, As5+ and V5+), single crystals of the novel compound dicadmium copper(II) bis[phosphate(V)], Cd2Cu(PO4)2, were obtained. This compound belongs to a small group of compounds adopting a Cu3(PO4)2‐type structure and having the general formula M12M2(XO4)2 (M1/M2 = Cd2+, Cu2+, Mg2+ and Zn2+; X = As5+, P5+ and V5+). The crystal structure is characterized by the interconnection of infinite [Cu(PO4)2]n chains and [Cd2O10]n double chains, both extending along the a axis. Exceptional characteristics of this structure are its novel chemical composition and the occurrence of double chains of CdO6 polyhedra that were not found in related structures. In contrast to the isomorphous compounds, where the M1 cations are coordinated by five O atoms, the Cd atom is coordinated by six. The dissimilarity in the geometry of M1 coordination between Cd2Cu(PO4)2 and the isomorphous compounds is mostly due to the larger ionic radius of the Cd cation in comparison with the Cu, Mg and Zn cations. Sharing a common edge, two CdO6 polyhedra form Cd2O10 dimers. Each such dimer is bonded to another dimer sharing common vertices, forming [Cd2O10]n double chains in the [100] direction. The Cu atoms, located on an inversion centre (site symmetry ), form isolated CuO4 squares interconnected by PO4 tetrahedra, forming [Cu(PO4)2]n chains similar to those found in related structures. Conversely, the [Cd2O10]n double chains, which were not found in related structures, are an exclusive feature of this structure. 相似文献
20.
Omer Andac Serkan Guney Yildiray Topcu Veysel T. Yilmaz William T. A. Harrison 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):m17-m20
Bis(pyridine‐2,6‐dimethanol‐N,O,O′)cobalt(II) disaccharinate dihydrate, [Co(C7H9NO2)2](C7H4NO3S)2·2H2O, (I), and bis(pyridine‐2,6‐dimethanol‐N,O,O′)copper(II) disaccharinate dihydrate, [Cu(C7H9NO2)2](C7H4NO3S)2·2H2O, (II), collectively [M(dmpy)2](sac)2·2H2O (where M is CoII or CuII, sac is the saccharinate anion and dmpy is pyridine‐2,6‐dimethanol), are isostructural. The [M(dmpy)2]2+ cations exhibit distorted octahedral geometry in which the two neutral dmpy species act as tripodal N,O,O′‐tridentate ligands. The crystal packing is determined by hydrogen bonding, as well as by weak pyridine–saccharinate π–π‐stacking interactions. 相似文献