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1.
In recent years, N‐heterocyclic carboxylate ligands have attracted much interest in the preparation of new coordination polymers since they contain N‐atom donors, as well as O‐atom donors, and have a rich variety of coordination modes which can lead to polymers with intriguing structures and interesting properties. A new two‐dimensional coordination polymer, namely poly[[μ3‐2,2′‐(1,2‐phenylene)bis(4‐carboxy‐1H‐imidazole‐5‐carboxylato)‐κ6O4,N3,N3′,O4′:O5:O5′]manganese(II)], [Mn(C16H8N4O8)]n or [Mn(H4Phbidc)]n, has been synthesized by the reaction of Mn(OAc)2·4H2O (OAc is acetate) with 2,2′‐(1,2‐phenylene)bis(1H‐imidazole‐4,5‐dicarboxylic acid) (H6Phbidc) under solvothermal conditions. In the polymer, each MnII ion is six‐coordinated by two N atoms from one H4Phbidc2− ligand and by four O atoms from three H4Phbidc2− ligands, forming a significantly distorted octahedral MnN2O4 coordination geometry. The MnII ions are linked by hexadentate H4Phbidc2− ligands, leading to a two‐dimensional structure parallel to the ac plane. In the crystal, adjacent layers are further connected by N—H…O hydrogen bonds, forming a three‐dimensional structure in the solid state.  相似文献   

2.
4‐Hydroxypyridine‐2,6‐dicarboxylic acid (chelidamic acid, hypydc[H]H2) reacts with MnCl2·2H2O in the presence of piperazine in water to afford the title complex, {[Mn3(C7H2NO5)2(H2O)8]·3H2O}n or {[Mn3(hypydc)2(H2O)8]·3H2O}n. This compound is a one‐dimensional coordination polymer, with the twofold symmetric repeat unit containing three metal centres. Two different coordination geometries are observed for the two independent MnII metal centres, viz. a distorted pentagonal bipyramid and a distorted octahedron. The 4‐oxidopyridine‐2,6‐dicarboxylate anions and two of the water molecules act as bridging ligands. The zigzag‐like geometry of the coordination polymer is stabilized by hydrogen bonds. O—H...O and C—H...O hydrogen bonds and water clusters consolidate the three‐dimensional network structure.  相似文献   

3.
The crystal structure of the title compound, tetra­chloro­[μ‐1,1,4,7,7‐pentakis(1H‐benzimidazol‐2‐yl­methyl)‐1,4,7‐tri­azaheptane]­dimanganese(II) methanol pentasolvate tetrahydrate, [Mn2Cl4(C44H43N13)]·5CH4O·4H2O, contains an ­asymmetric dinuclear MnII–DTPB [DTPB is 1,1,4,7,7‐pentakis(1H‐benzimidazol‐2‐yl­methyl)‐1,4,7‐tri­aza­heptane] complex with an intra‐ligand bridging group (–NCH2CH2N–), as well as several solvate mol­ecules (methanol and water). Both MnII cations have similar distorted octahedral coordination geometries. One MnII cation is coordinated by a Cl anion and five N atoms from the ligand, and the other is coordinated by three Cl anions and three N atoms of the same ligand. The Mn⋯Mn distance is 7.94 Å. A Cl⋯H—O⋯H—O⋯H—N hydrogen‐bond chain is also observed, connecting the two parts of the complex.  相似文献   

4.
The tape‐like chain {[(tptz)MnII(H2O)MnIII(CN)6]2MnII(H2O)2}n?4n MeOH?2n H2O based on the anisotropic building block hexacyanomanganate(III) exhibits long‐range magnetic ordering below 5.1 K as well as single‐chain magnetic behavior at lower temperatures with an effective energy barrier of 40.5(7) K.  相似文献   

5.
Single crystals of (1,3‐diamino‐5‐azaniumyl‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)lithium(I) diiodide dihydrate, [Li(C6H16N3O3)(C6H15N3O3)]I2·2H2O or [Li(Htaci)(taci)]I2·2H2O (taci is 1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol), (I), bis(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)sodium(I) iodide, [Na(C6H15N3O3)2]I or [Na(taci)2]I, (II), and bis(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)potassium(I) iodide, [K(C6H15N3O3)2]I or [K(taci)2]I, (III), were grown by diffusion of MeOH into aqueous solutions of the complexes. The structures of the Na and K complexes are isotypic. In all three complexes, the taci ligands adopt a chair conformation with axial hydroxy groups, and the metal cations exhibit exclusive O‐atom coordination. The six O atoms of the resulting MO6 unit define a centrosymmetric trigonal antiprism with approximate D3d symmetry. The interligand O...O distances increase significantly in the order Li < Na < K. The structure of (I) exhibits a complex three‐dimensional network of R—NH2—H...NH2R, R—O—H...NH2R and R—O—H...O(H)—H...NH2R hydrogen bonds. The structures of the Na and K complexes consist of a stack of layers, in which each taci ligand is bonded to three neighbours via pairwise O—H...NH2 interactions between vicinal HO—CH—CH—NH2 groups.  相似文献   

6.
The mixed‐amide phosphinates, rac‐phenyl (N‐methylcyclohexylamido)(p‐tolylamido)phosphinate, C20H27N2O2P, (I), and rac‐phenyl (allylamido)(p‐tolylamido)phosphinate, C16H19N2O2P, (II), were synthesized from the racemic phosphorus–chlorine compound (R,S)‐(Cl)P(O)(OC6H5)(NHC6H4p‐CH3). Furthermore, the phosphorus–chlorine compound ClP(O)(OC6H5)(NH‐cyclo‐C6H11) was synthesized for the first time and used for the synthesis of rac‐phenyl (benzylamido)(cyclohexylamido)phosphinate, C19H25N2O2P, (III). The strategies for the synthesis of racemic mixed‐amide phosphinates are discussed. The P atom in each compound is in a distorted tetrahedral (N1)P(=O)(O)(N2) environment. In (I) and (II), the p‐tolylamido substituent makes a longer P—N bond than those involving the N‐methylcyclohexylamido and allylamido substituents. In (III), the differences between the P—N bond lengths involving the cyclohexylamido and benzylamido substituents are not significant. In all three structures, the phosphoryl O atom takes part with the N—H unit in hydrogen‐bonding interactions, viz. an N—H...O=P hydrogen bond for (I) and (N—H)(N—H)...O=P hydrogen bonds for (II) and (III), building linear arrangements along [001] for (I) and along [010] for (III), and a ladder arrangement along [100] for (II).  相似文献   

7.
Three 3‐amino‐1, 2, 4‐triazole (atz)‐based paramagnetic complexes, [Mn(atz)(pa)]n ( 1 ), {[Mn(atz)1.5(hip)] · H2O}n ( 2 ), and [Mn(H2O)2(atz)2(nb)2] ( 3 ) (H2pa = o‐phthalic acid, H2hip = 5‐hydroxylisophthalic acid, and Hnb = p‐nitrobenzoic acid) were prepared by introducing different carboxylate‐containing aromatic coligands, and structurally and magnetically characterized. Helical MnII‐atz and bent MnII‐pa2– chains are crosslinked by sharing the same metal sites to generate a honeycomb‐shaped framework of 1 . The undulated MnII‐atz layers constructed from 22‐member metallomacrocycles are periodically supported by ditopic hip2– ligands to lead to a pillared‐layer structure of 2 . In contrast, complex 3 is a centrosymmetric mononuclear entity, which is assembled into a three‐dimensional supramolecular network by abundant hydrogen‐bonding interactions. The structural difference of 1 – 3 is significantly due to the combinations of the flexible coordination modes adopted by the mixed atz and carboxylate groups. Weak and comparable antiferromagnetic couplings are observed in the nearest neighbors of 1 – 3 , which are cooperatively transmitted either by short carboxylate and/or atz heterobridges or by weak non‐covalent interactions.  相似文献   

8.
The irreversible inhibition of δ‐chymotrypsin with the enantiomerically pure, P(3)‐axially and P(3)‐equatorially X‐substituted cis‐ and trans‐configurated 2,4‐dioxa‐3‐phospha(1,5,5‐2H3)bicyclo[4.4.0]decane 3‐oxides (X=F, 2,4‐dinitrophenoxy) was monitored by 31P‐NMR spectroscopy. 1H‐Correlated 31P{2H}‐NMR spectra enabled the direct observation of the vicinal coupling (3J) between the P‐atom of the inhibitor and the CH2O moiety of Ser195 (=‘Ser195’(CH2O)), thus establishing the covalent nature of the ‘Ser195’(CH2O? P) bond in the inhibited enzyme. The stereochemical course of the phosphorylation is dependent on the structure of the inhibitor, and neat inversion, both inversion and retention, as well as neat retention of the configuration at the P‐atom was found.  相似文献   

9.
The analysis of 17O NMR transverse relaxation rates and EPR transverse electronic relaxation rates for aqueous solutions of the four DTPA‐like (DTPA = diethylenetriamine‐N,N,N,N″,N″‐pentaacetic acid) complexes, [Gd(DTPA‐PY)(H2O)]? (DTPA‐PY = N′‐(2‐pyridylmethyl)), [Gd(DTPA‐HP)(H2O)2]? (DTPA‐HP = N′‐(2‐hydroxypropyl)), [Gd(DTPA‐H1P)(H2O)2]? (DTPA‐H1P = N′‐(2‐hydroxy‐1‐phenylethyl)) and [Gd(DTPA‐H2P)(H2O)2] (DTPA‐H2P = N′‐(2‐hydroxy‐2‐phenylethyl)), at various temperatures allows us to understand the water exchange dynamics of these four complexes. The water‐exchange lifetime (τM) parameters for [Gd(DTPA‐PY)(H2O)]?, [Gd(DTPA‐HP)(H2O)2]?, [Gd(DTPA‐H1P)(H2O)2]? and [Gd(DTPA‐H2P)(H2O)2] are of 585, 98, 163, and 69 ns, respectively. Compared with [Gd(DTPA)(H2O)]2? (τM = 303 ns), the τM value of [Gd(DTPA‐PY)(H2O)]? is slightly higher, but the other three complexes values are significantly lower than those of [Gd(DTPA)(H2O)]2?. This difference is explained by the fact that the gadolinium(III) complexes of DTPA‐HP, DTPA‐H1P, and DTPA‐H2P have two inner‐sphere waters. The 2H longitudinal relaxation rates of the labeled diamagnetic lanthanum complex allow the calculation of its rotational correlation time (τR). The τR values calculated for DTPA‐PY, DTPA‐HP, DTPA‐H1P, and DTPA‐H2P are of 127, 110, 142 and 147 ps, respectively. These four values are higher than the value of [La(DTPA)]2? (τR = 103 ps), because the rotational correlation time is related to the magnitude of its molecular weight.  相似文献   

10.
In the title coordination polymer, catena‐poly[[dichloridomanganese(II)]‐μ‐1,1‐diphenyl‐3,3′‐[(1R,2R)‐cyclohexane‐1,2‐diylbis(azaniumylylidene)]dibut‐1‐en‐1‐olate‐κ2O:O′], [MnCl2(C26H30N2)]n, synthesized by the reaction of the chiral Schiff base ligand 1,1‐diphenyl‐3,3′‐[(1R,2R)‐cyclohexane‐1,2‐diylbis(azanediyl)]dibut‐2‐en‐1‐one (L) with MnCl2·4H2O, the asymmetric unit contains one crystallographically unique MnII ion, one unique spacer ligand, L, and two chloride ions. Each MnII ion is four‐coordinated in a distorted tetrahedral coordination environment by two O atoms from two L ligands and by two chloride ligands. The MnII ions are bridged by L ligands to form a one‐dimensional chain structure along the a axis. The chloride ligands are monodentate (terminal). The ligand is in the zwitterionic enol form and displays intramolecular ionic N+—H...O hydrogen bonding and π–π interactions between pairs of phenyl rings which strengthen the chains.  相似文献   

11.
A novel manganese coordination polymer, poly[(μ5‐thiophene‐3,4‐dicarboxylato)manganese(II)], [Mn(C6H2O4S)]n, was synthesized hydrothermally using 3,4‐thiophenedicarboxylate (3,4‐tdc2−) as the organic linker. The asymmetric unit of the complex contains an Mn2+ cation and one half of a deprotonated 3,4‐tdc2− anion, both residing on a twofold axis. Each Mn2+ centre is six‐coordinated by O atoms of bridging/chelating carboxylate groups from five 3,4‐tdc2− anions, forming a slightly distorted octahedron. The Mn2+ centres are bridged by 3,4‐tdc2− anions to give an infinite two‐dimensional layer which incorporates one‐dimensional Mn–O gridlike chains, and in which the 3,4‐tdc2− anion adopts a novel hexadentate chelating and μ5‐bridging coordination mode. The fully deprotonated 3,4‐tdc2− anion exhibits unexpected efficiency as a ligand towards the Mn2+ centres, which it coordinates through all of its carboxylate O atoms to provide the novel coordination mode. The IR spectrum of the complex is also reported.  相似文献   

12.
In the title compound, [Mn(C5H2N2O4)(C12H9N3)2]·H2O, the MnII centre is surrounded by three bidentate chelating ligands, namely, one 6‐oxido‐2‐oxo‐1,2‐dihydropyrimidine‐5‐carboxylate (or uracil‐5‐carboxylate, Huca2−) ligand [Mn—O = 2.136 (2) and 2.156 (3) Å] and two 2‐(2‐pyridyl)‐1H‐benzimidazole (Hpybim) ligands [Mn—N = 2.213 (3)–2.331 (3) Å], and it displays a severely distorted octahedral geometry, with cis angles ranging from 73.05 (10) to 105.77 (10)°. Intermolecular N—H...O hydrogen bonds both between the Hpybim and the Huca2− ligands and between the Huca2− ligands link the molecules into infinite chains. The lattice water molecule acts as a hydrogen‐bond donor to form double O...H—O—H...O hydrogen bonds with the Huca2− O atoms, crosslinking the chains to afford an infinite two‐dimensional sheet; a third hydrogen bond (N—H...O) formed by the water molecule as a hydrogen‐bond acceptor and a Hpybim N atom further links these sheets to yield a three‐dimensional supramolecular framework. Possible partial π–π stacking interactions involving the Hpybim rings are also observed in the crystal structure.  相似文献   

13.
A metal coordination polymer, {[Mn2Mo(CN)8(C12H8N6)(CH3CN)2(H2O)2]·2H2O}n, has been synthesized by the reaction of Mn(ClO4)2·6H2O with 3,6‐bis(pyridin‐2‐yl)‐1,2,4,5‐tetrazine (bptz) and (Bu3N)3[Mo(CN)8] at room temperature. The polymer was characterized by IR spectroscopy, elemental analysis and X‐ray diffraction, and the magnetic properties were also investigated. The X‐ray diffraction analysis reveals that the compound is a new three‐dimensional coordination polymer with a PtS‐type network. Magnetic investigation shows antiferromagnetic coupling between adjacent Mn2+ cations.  相似文献   

14.
In the title complex, [Mn(C5H4NO)2(C5H5NO)2]n or [Mn(μ‐3‐PyO)2(3‐PyOH)2]n (3‐PyO is the pyridin‐3‐olate anion and 3‐PyOH is pyridin‐3‐ol), the MnII atom lies on an inversion centre and has octahedral geometry, defined by two N atoms and two deprotonated exocyclic O atoms of symmetry‐related pyridin‐3‐olate ligands [Mn—N = 2.3559 (14) Å and Mn—O = 2.1703 (11) Å], as well as two N atoms of terminal 3‐PyOH ligands [Mn—N = 2.3482 (13) Å]. The MnII atoms are bridged by the deprotonated pyridin‐3‐olate anion into a layer structure, generating sheets in the (01) plane. These sheets are linked by O—H⋯O hydrogen bonds. There are also π–π and C—H⋯π interactions in the crystal structure.  相似文献   

15.
Two complexes based on the ligand 1,4‐dihydro‐2,3‐quinoxalinedione, namely [Mn(H2L)2(H2O)2]n ( 1 ) and {[Zn2(H2L)2(tz)2] · 5H2O}n ( 2 ) (H3L = 2,3‐dioxo‐1,2,3,4‐tetrahydroquinoxaline‐6‐carboxylic acid, Htz = 1,2,4‐triazole) were hydrothermally synthesized and characterized by elemental analyses, IR spectroscopy, as well as single‐crystal and powder X‐ray diffraction. Complex 1 exhibited a 1D comb‐like chain formed by H2L anions linking MnII ions, whereas complex 2 was a 2D layer‐like structure with square‐shaped windows and outstretched arms built by combination of H2L and tz ligands with ZnII ions. The adjacent chains or layers connected with each other by intermolecular hydrogen bonding and π–π stacking to further extend to a 3D supermolecular framework. In addition, the thermal stabilities, luminescence properties, and optical energy gap of 1 and 2 were investigated in detail.  相似文献   

16.
The title racemic heterometallic dinuclear compound, [MnSn(C2H2O2S)3(H2O)5], (I), contains one main group SnIV metal centre and one transition metal MnII centre, and, by design, links the MnII centre to the building unit of the (Δ/Λ) [SnL3]2− complex anion (L is the 2‐sulfidoacetate dianion). In this cluster, the SnIV centre of the (Δ/Λ) [SnL3]2− unit is coordinated by three O atoms and three S atoms from three L ligands to form an [SnO3S3] octahedral coordination environment. The MnII centre is in an [MnO6] octahedral coordination environment, with five O atoms from five water molecules and the sixth from the μ2L ligand of the (Δ/Λ) [SnL3]2− unit. Between adjacent dinuclear molecules, there are many hydrogen‐bond interactions of O—H...O, O—H...S, C—H...O and C—H...S types. Of these, eight pairs of O—H...O hydrogen bonds fuse all the dinuclear molecules into two‐dimensional supramolecular sheets along the bc plane. Adjacent supramolecular sheets are further connected through O—H...S hydrogen bonds to give a three‐dimensional supramolecular network.  相似文献   

17.
In the title two‐dimensional coordination polymer, [Mn(1,4‐BDOA)(4,4‐bipy)(H2O)2]n [1,4‐BDOA2− is the p‐phenyl­ene­dioxy­di­acetate dianion (C10H8O6) and 4,4‐bipy is 4,4‐bi­pyridine (C10H8N2)], each MnII atom displays octahedral coordination by two O atoms of the 1,4‐BDOA2− groups, two N atoms of the 4,4‐bipy ligands and two solvent water mol­ecules. The MnII atom, 4,4‐bipy ligand and 1,4‐BDOA2− group occupy different inversion centres. Adjacent MnII atoms are bridged by 1,4‐BDOA2− groups and 4,4‐bipy ligands, forming a two‐dimensional network with Mn⋯Mn separations of 11.592 (2) and 11.699 (2) Å. Hydro­gen bonds from a water O—H group link the layers in the third dimension.  相似文献   

18.
The synthesis, crystal structure, and magnetic properties of a [MnIII3MnII3‐O)(mbp)3(OAc)3] · 4H2O ( 1 ) [H2mbp = 2‐(1H‐benzimidazol‐2‐yl)‐2‐ methylpropane‐1,3‐diol] cluster are reported herein. Mn ions in compound 1 have a tetrahedron topology. Solid‐state direct current and alternating current magnetic susceptibility measurements on compound 1 reveal a ground state with ST = 7/2 as well as the probable single‐molecule magnetic behavior.  相似文献   

19.
Reaction of [Au(DAPTA)(Cl)] with RaaiR’ in CH2Cl2 medium following ligand addition leads to [Au(DAPTA)(RaaiR’)](Cl) [DAPTA=diacetyl-1,3,5-triaza-7-phosphaadamantane, RaaiR’=p-R-C6H4-N=N- C3H2-NN-1-R’, (1—3), abbreviated as N,N’-chelator, where N(imidazole) and N(azo) represent N and N’, respectively; R=H (a), Me (b), Cl (c) and R’=Me (1), CH2CH3 (2), CH2Ph (3)]. The 1H NMR spectral measurements in D2O suggest methylene, CH2, in RaaiEt gives a complex AB type multiplet while in RaaiCH2Ph it shows AB type quartets. 13C NMR spectrum in D2O suggest the molecular skeleton. The 1H-1H COSY spectrum in D2O as well as contour peaks in the 1H-13C HMQC spectrum in D2O assign the solution structure.  相似文献   

20.
The title complex, {[Ni(C15H11N4O2S)2(C10H8N2)(H2O)2]·H2O}n, was synthesized by the reaction of nickel chloride, 4‐{[(1‐phenyl‐1H‐tetrazol‐5‐yl)sulfanyl]methyl}benzoic acid (HL) and 4,4′‐bipyridine (bpy) under hydrothermal conditions. The asymmetric unit contains two half NiII ions, each located on an inversion centre, two L ligands, one bpy ligand, two coordinated water molecules and one unligated water molecule. Each NiII centre is six‐coordinated by two monodentate carboxylate O atoms from two different L ligands, two pyridine N atoms from two different bpy ligands and two terminal water molecules, displaying a nearly ideal octahedral geometry. The NiII ions are bridged by 4,4′‐bipyridine ligands to afford a linear array, with an Ni...Ni separation of 11.361 (1) Å, which is further decorated by two monodentate L ligands trans to each other, resulting in a one‐dimensional fishbone‐like chain structure. These one‐dimensional fishbone‐like chains are further linked by O—H...O, O—H...N and C—H...O hydrogen bonds and π–π stacking interactions to form a three‐dimensional supramolecular architecture. The thermal stability of the title complex was investigated via thermogravimetric analysis.  相似文献   

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