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1.
H. Y. Liu G. W. Li Z. L. Li J. Y. Wu Y. C. Cai 《Russian Journal of Coordination Chemistry》2011,37(9):668-673
Two new zinc(II) complexes, [ZnBr2L1] (I) and [ZnBr2L2] (II), where L1 is 2-[(2-isopropylaminoethylimino)methyl]-5-methoxyphenol and L2 is N,N-dimethyl-N′-(1-pyridin-2-yl-ethylidene)ethane-1,2-diamine, were prepared and characterized using elemental analysis,
FT-IR spectroscopy, and X-ray single-crystal diffraction. In complex I, the Zn(II) atom is coordinated by one phenolic O and
one imino N atoms of L1 and two Br atoms, forming a tetrahedral coordination geometry. In complex II, the Zn(II) atom is in a trigonal bipyramidal coordination geometry with the equatorial plane formed by the imino N atom
of L2 and two Br atoms and with the two axial positions occupied by one pyridine N and one amino N atoms of L2. In the crystal structure of I, the mononuclear zinc complex molecules are linked through intermolecular N-H…O and N-H…Br
hydrogen bonds, forming chains running along the y axis. The chains are further linked via intermolecular C-H…Br hydrogen bonds. In the crystal structure of II, the mononuclear zinc complex molecules are linked through intermolecular C-H…Br hydrogen bonds, forming a 3D network. 相似文献
2.
Calculations of three structures of the 1-methyl-3-(trichlorogermyl)propionic acid molecule and its dimers were performed
at the RHF/6-31G(d) level with the full geometry optimization. According to the calculations, in this molecule in a gaseous
state the Ge atom is most likely pentacoordinated due to the Ge←O coordination interaction. The dimerization does not diminish,
but slightly increases the strength of Ge←O coordination bond. At the formation of the Ge←O bond the electron density on the
oxygen atom increases and on the Ge atom decreases. The comparison of the results of calculations with X-ray diffraction data
and with the 35Cl NQR spectrum shows that stereoelectronic structure of this compound in the crystalline and gaseous states are quite different. 相似文献
3.
RHF/6-31G(d) and MP2/6-31G(d) calculations were carried out to study the stereoelectronic structure of 1-(1-trichlorogermylethyl)pyrrolidin-2-one
with a pentacoordinated germanium atom. These results were compared with the X-ray diffraction structural analysis data. Upon
formation of the Ge ← O coordination bond in this molecule, the electron density of all the atoms of the coordination polyhedron
of the germanium atom, including the oxygen atom, increases, especially the axial chlorine atom, while the electron density
of the germanium, nitrogen, and carbonyl group carbon atoms decreases. Different polarization of all three valence p-orbitals
of each Cl atom of this molecule was established. 35Cl nuclear quadrupole resonance spectrum parameters were evaluated. The molecule also has stable form, in which the germanium
atom is tetracoordinated. The total energy of this form is 2.7 kcal/mol higher than for the structure with a pentacoordinated
germanium atom. 相似文献
4.
V. G. Avakyan L. E. Gusel’nikov S. L. Gusel’nikov V. F. Sidorkin 《Russian Chemical Bulletin》2005,54(9):2013-2022
The effect of the nature of substituents at sp2-hybridized silicon atom in the R2Si=CH2 (R = SiH3, H, Me, OH, Cl, F) molecules on the structure and energy characteristics of complexes of these molecules with ammonia, trimethylamine,
and tetrahydrofuran was studied by the ab initio (MP4/6-311G(d)//MP2/6-31G(d)+ZPE) method. As the electronegativity, χ, of the substituent R increases, the coordination bond
energies, D(Si← N(O)), increase from 4.7 to 25.9 kcal mol−1 for the complexes of R2Si=CH2 with NH3, from 10.6 to 37.1 kcal mol−1 for the complexes with Me3N, and from 5.0 to 22.2 kcal mol−1 for the complexes with THF. The n-donor ability changes as follows: THF ≤ NH3 < Me3N. The calculated barrier to hindered internal rotation about the silicon—carbon double bond was used as a measure of the
Si=C π-bond energy. As χ increases, the rotational barriers decrease from 18.9 to 5.2 kcal mol−1 for the complexes with NH3 and from 16.9 to 5.7 kcal mol−1 for the complexes with Me3N. The lowering of rotational barriers occurs in parallel to the decrease in D
π(Si=C) we have established earlier for free silenes. On the average, the D
π(Si=C) energy decreases by ∼25 kcal mol−1 for NH3· R2Si=CH2 and Me3N·R2Si=CH2. The D(Si←N) values for the R2Si=CH2· 2Me3N complexes are 11.4 (R = H) and 24.3 kcal mol−1 (R = F). sp2-Hybridized silicon atom can form transannular coordination bonds in 1,1-bis[N-(dimethylamino)acetimidato]silene (6). The open form (I) of molecule 6 is 35.1 and 43.5 kcal mol−1 less stable than the cyclic (II, one transannular Si←N bond) and bicyclic (III, two transannular Si←N bonds) forms of this molecule, respectively. The D(Si←N) energy for structure III was estimated at 21.8 kcal mol−1.
Dedicated to Academician N. S. Zefirov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1952–1961, September, 2005. 相似文献
5.
Calculations of 3-(trichlorogermyl)propanoylamide molecule containing a Ge←O coordination bond were performed by RHF/6-31G(d)
method with full and partial geometry optimization. Its total energy 2.22 kcal mol−1 is lower than that of the molecule with tetracoordinated germanium atoms. Germanium and oxygen atoms initiate the formation
of a coordination Ge←O bond in this molecule and are conductors of the electron density transfer from the atoms nearest to
the oxygen on the atoms of the germanium coordination polyhedron. No electron density transfer occurs from the oxygen atom
to germanium. Upon decrease in the Ge...O distance the axial Ge-Cl bond is polarized much stronger than the equatorial bonds.
In the crystalline state of the substance these molecules are fixed in an energetically unfavorable structure. 相似文献
6.
The molecular and electronic structure features of silatranes, germatranes, and their carbon analogs
M. V. Zabalov S. S. Karlov G. S. Zaitseva D. A. Lemenovskii 《Russian Chemical Bulletin》2006,55(3):464-476
Molecular geometries of fifty-six metallatranes N(CH2CH2Y)3M-X and fifty-six carbon analogs HC(CH2CH2Y)3M-X (M = Si, Ge; X = H, Me, OH, F; Y = CH2, O, NH, NMe, NSiMe3, PH, S) were optimized by the DFT method. Correlations between changes in the bond orbital populations, electron density
ρ(r), electron density laplacian ∇2ρ(r), |λ1|/λ3 ratio, electronic energy density E(r), bond lengths, and displacement of the central atom from the plane of three equatorial substituents and the nature of substituents
X and Y were studied. As the number of electronegative substituents at the central atom increases, the M←N, M-X, and M-Y bond
lengths decrease, while the M←N bond strength and the electron density at critical points of the M←N, M-X, and M-Y bonds increase.
An increase in electronegativity of a substituent (X or Y) is accompanied by a decrease in the ionicities of the other bonds
(M-X, M-Y, and M←N) formed by the central atom (Si, Ge). A new molecular orbital diagram for bond formation is proposed, which
takes into account the interaction of all five substituents at the central atom (M = Si, Ge) in atrane molecules.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 448–460, March, 2006. 相似文献
7.
《Journal of Coordination Chemistry》2012,65(3):433-439
Abstract A new zinc bromide complex of a Schiff-base ligand derived from thiosemicarbazide and 4-methoxylphenyldehyde, which shows ca 13 times better SHG efficiency than urea, has been prepared and characterized. Single crystal X-ray diffraction analysis established that the coordination geometry about the zinc atom is tetrahedral with two equivalent Zn-Br and Zn-S bonds. The Schiff-base ligand is coordinated to the Zn(II) via the monodentate mercapto sulfur atom. The polar structure (space group Aba2) is stabilized by hydrogen bonds between the oxygen atom and the amino nitrogen atoms N(l). The complex crystallizes in the orthorhombic space group Aba2 with cell parameters a=11.970(2), b = 21.888(2), c= 9.157(2)Å and Z = 4. The structure was solved by direct methods and refined by full-matrix least-squares to R = 0.065 and R w = 0.117 for the 722 observed reflections with I > 2[sgrave](I). 相似文献
8.
V. V. Davydov V. I. Sokol N. V. Rychagina R. V. Linko M. A. Ryabov Yu. V. Shklyaev V. S. Sergienko 《Russian Journal of Inorganic Chemistry》2009,54(6):893-905
The reaction of 1-hydrazino-3,3-dimethyl-3,4-dihydroisoquinoline with 9,10-phenanthrenequinone gave (9E)-phenanthrene-9,10-dione[(1Z)-3,3-dimethyl-3,4-dihydroisoquinolin-1(2H)-ylidene]hydrazone (L). The reaction of L with copper(II) bromide gave the complex (LH)[CuBr2]. The crystal structures of the monohydrate L · H2O (I) and the isolated complex (LH)[CuBr2] (II) were determined by X-ray diffraction. The structural units of I are pseudo-centrosymmetric dimers in which the L and water molecules are combined by strong hydrogen bonds. The active H
atom is located at the N(1) atom of the isoquinoline fragment of the L molecule. The L molecule occurs in the crystal as the
cis, trans isomer with respect to exocyclic C=N bonds at the isoquinoline and phenanthrenequinone fragments, respectively. Complex II has a cation-anion structure. The LH+ cation as the cis, cis isomer is protonated at N(2) and stabilized by two intramolecular hydrogen bonds. In the CuBr2− anion, the copper atom in the oxidation state +1 has a linear coordination, the C-Br bond length is 2.185(4) ± 0.005 ?, and
the BrCuBr angle is 179.8(4)°. The main ion-ion interactions in structure II are shortened contacts involving bromine atoms, which combine cations and anions into a three-dimensional framework.
Original Russian Text ? V.V. Davydov, V.I. Sokol, N.V. Rychagina, R.V. Linko, M.A. Ryabov, Yu.V. Shklyaev, V.S. Sergienko,
2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 6, pp. 958–970. 相似文献
9.
S. N. Adamovich R. G. Mirskov A. N. Mirskova M. G. Voronkov 《Russian Journal of General Chemistry》2010,80(10):1972-1973
Reaction of tris(2-hydroxyethyl)amine hydrochloride Cl− N+H(CH2CH2OH)3 with zinc diacetate and bis(2-methylphenoxy)acetate in the molar ratio 2: 1 results in complexes 2[Cl− N+H(CH2CH2OH)3]· Zn (OCOR)2 (I, II) R= Me (I), 2-MeC6H4OCH2 (II), which contain two protatrane cations linked with zinc diacylate by two coordination bonds HO → Zn. Complexes I and II are also formed by the reaction of the corresponding tris(2-hydroxyethyl)amine hydrochloride acylate RCOO−N+H(CH2CH2OH)3 with ZnCl2. The structure of complexes I, II is proved by elemental analysis, IR and 1H, 13C, 15N NMR spectroscopy. 相似文献
10.
V. V. Davydov V. I. Sokol N. V. Rychagina R. V. Linko Yu. V. Shklyaev V. S. Sergienko 《Russian Journal of Inorganic Chemistry》2011,56(5):680-686
The complex [Ni(L-H)2] · CHCl3 (I), where L-H is the (9E)-phenanthrene-9,10-dione[(1Z)-3,3-dimethyl-3,4-dihydroisoquinolin-1(2H)-ylidene]hydrazone anion (L),
was synthesized for the first time. The crystal structure of I was solved. The L-H and L-H′ anions exist as cis- and trans-isomers and are linked to the central Ni2+ atom in a tridentate chelating mode giving rise to two conjugated five-membered metal rings of different composition (NiN3C and NiONC2) at each anion. The Ni2+ coordination polyhedron is a highly distorted octahedron whose axial positions are occupied by N(3) and N(3)′ atoms. The
vertices of the tetrahedrally distorted equatorial base of the octahedron are occupied by the N(1) and N(1)′ atoms of the
dihydroisoquinoline fragment (A) and the O(1) and O(1)′ atoms of the phenanthrenequinone fragment (B). Complex I occurs as the cis-isomer. The conformations of the L-H anions in I and the L molecules in L · H2O do not differ much. The randomly disordered CHCl3 solvent molecules in I occupy crystal voids between the centrosymmetric dimeric associates. Spectroscopic (IR and UV-Vis) characteristics of I were obtained. 相似文献
11.
L. V. Baikalova V. I. Sokol V. N. Khrustalev E. A. Zel'bst B. A. Trofimov 《Russian Journal of General Chemistry》2005,75(9):1469-1474
The crystal and molecular structure of bis(1-vinylimidazole)diacetatozinc (C14H18N4O4Zn), a highly effective antidote and antihypoxic drug, was determined [R1 0.0335 for 8902 unique reflections with I > 2σ(I) and wR2 0.0931 for all 10 752 unique reflections]. The triclinic unit cell contains two independent molecules of the complex, A and B. These molecules have short contacts O?H-C. The zinc atoms in molecules A and B have distorted tetrahedral coordination with the coordination sites occupied by the imidazole nitrogen atoms and acetate oxygen atoms. The lengths of the Zn-N bonds (2.019–2.050 Å) and Zn-O bonds with three acetate groups (1.956–1.958 Å) are typical for zinc complexes, whereas the Zn-O3 bond with one of the acetate groups in molecule A is somewhat longer, 2.009(1) Å; also, there is an additional contact of the zinc atom with the carbonyl oxygen atom of this group (Zn-O4 2.498 Å). 相似文献
12.
Alper Tolga ?olak Okan Zafer Yeilel Tuncer H?kelek Ertan ahin 《Structural chemistry》2008,19(2):285-290
A novel metal–organic coordination polymer framework formulated as {[Zn(dipic)(μ-en)]·3H2O}
n
(1) (catena-poly-μ-ethylenediamine(dipicolinato)zinc(II) trihydrate) has been synthesized and characterized by spectral method (IR), elemental
analysis, thermal analysis (TG, DTG, DTA) and single crystal X-ray diffraction techniques. It crystallizes in the triclinic
system, space group P−1. The asymmetric unit contains three hydrogen-bonded water molecules and the Zn atom is five-coordinated by three N and
two O atoms. In fact, it is a new one-dimensional zinc complex with the peculiarity of having the ethylenediamine ligand very
unusually acting as bridge to form polymeric chains. In the crystal structure, intramolecular O–H···O and intermolecular O–H···O
and N–H···O hydrogen bonds result in the formation of a supramolecular structure, in which they seem to be effective in the
stabilization of the structure. 相似文献
13.
Sokol V. I. Davydov V. V. Elekhina N. A. Shklyaev Yu. V. Sergienko V. S. 《Russian Journal of Coordination Chemistry》2002,28(6):439-449
1-(3,3-Dimethyl-3,4-dihydroisoquinoline-1-yl)-1-(quinoline-2-yl)methane (I) is studied using X-ray diffraction analysis. Molecule I is shown to have a flattened structure and to exist in the enamine tautomeric form: the active hydrogen atom is at the N(1) atom of the dihydroisoquinoline fragment. Molecule I is stabilized by the N–H...N intramolecular hydrogen bond. 相似文献
14.
A. D. Khalaji S. Jalali Akerdi G. Grivani H. Stoeckli-Evans D. Das 《Russian Journal of Coordination Chemistry》2011,37(8):578-584
New Symmetric bidentate Schiff-base ligands N,N′-bis(2,3,4-trimethoxybenzylidene)-1,2-di-aminoethane, (234-MeO-Ba)2En, and its corresponding zinc(II) and mercury(II) complexes, Zn((234-MeO-Ba)2En)I2 (I), Hg((234-MeO-Ba)2En)Cl2 (II) have been synthesized and characterized by elemental analyses (CHN), FT-IR and 1H NMR spectroscopy. The thermal behaviors
of complexes were study using thermogravimetry in order to evaluate their thermal stability and thermal decomposition pathways.
The crystal structure of I was determined from single-crystal X-ray diffraction. The coordination polyhedron about the zinc(II) center in complex I is best described as a distorted tetrahedron. 相似文献
15.
S. I. Orysyk L. N. Rybachuk V. I. Pekhnyo V. V. Orysyk 《Russian Journal of Inorganic Chemistry》2011,56(11):1747-1751
New Pd(II) complexes with 1-allyl-3-(2-pyridyl)thiourea (APTU) of the formulas [Pd(C9H11N3S)Cl2] (I) and [Pd(C9H11N3S)2]Cl2 (II) were obtained and examined by UV-Vis, IR, and 1H NMR spectroscopy. The conditions for the complexation reactions were optimized.
The instability constants and molar absorption coefficients of these complexes were calculated. Comparison of the characteristic
bands in the UV-Vis and IR spectra of the complexes and free APTU revealed that the ligand in both complexes is coordinated
to the metal atom in the thione form in the bidentate chelating mode through the S atom of the thiourea group and the pyridine
N atom. In the UV-Vis spectra of the complexes, the charge transfer bands (π → π* Py) and n → π* (C=NPy), (C=S) experience hypsochromic shifts by 450–470 cm−1 caused by the coordination of APTU to the metal ion, which gives rise to ligand-metal charge-transfer bands (C=NPy → Pd, n → π* (C=S)) and (SPd). The protons in the 6-, 4-, and 3-positions of the pyridine ring and the thiourea NH proton in the
chelate ring are most sensitive to the complexation. 相似文献
16.
A. Yu. Tsivadze L. Kh. Minacheva I. S. Ivanova V. E. Baulin E. N. Pyatova V. S. Sergienko 《Russian Journal of Inorganic Chemistry》2008,53(4):545-551
The syntheses of the complex copper salt CuL2 · 2H2O (I) and the erbium nitrate complex Er(NO3)3 · 2HL · 2H2O (II) (HL is 2-[2′-(oxymethyldiphenylphosphinyl)phenyldiazenyl]-4-tert-butylphenol) have been described. Basic vibrational frequencies in the IR spectra of I and II have been interpreted. The crystal structure of I has been determined by X-ray crystallography: the crystals are monoclinic, a = 15.157(3) ?, b = 17.080(2) ?, c = 22.451(9) ?, β = 106.09(3)°, V = 5584(3) ?3, Z = 4, space group C2/c, R = 0.0546 (for 1152 reflections with I > 2σ(I)). The coordination polyhedron of the copper atom (symmetry C
2) can be described as a symmetrically elongated square bipyramid (4+2). The basic square of the Cu polyhedron is formed by
the oxygen atom of the substituted phenol and one of the nitrogen atoms of the azo group of each of the two deprotonated ligands
L− (Cu-N, 1.969(6) ?; Cu-O, 1.899(5) ?). The angles between the opposite O and N atoms are 157.6°, and the other equatorial
angles are in the range 90.6°–95.9°. The axial positions are occupied by the anisole O(2) and O(2A) atoms (Cu-O, 2.737(6)
?, the O(2)Cu(1)O(2A) angle, 132.3°). In the crystal of I, complex molecules and water molecules of crystallization are combined by a system of hydrogen bonds. IR spectra show that,
in complex II, as distinct from compound I, the HL ligand is coordinated to the erbium atom through the phosphoryl oxygen atom.
Original Russian Text ? A.Yu. Tsivadze, L.Kh. Minacheva, I.S. Ivanova, V.E. Baulin, E.N. Pyatova, V.S. Sergienko, 2008, published
in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 4, pp. 601–607. 相似文献
17.
Yu. M. Chumakov V. I. Tsapkov Yu. A. Simonov B. Ya. Antosyak G. Bocelli M. Perrin Z. A. Starikova N. M. Samus A. P. Gulea 《Russian Journal of Coordination Chemistry》2005,31(8):588-596
The crystal structures of copper(II) nitrate complexes with 2-(2-hydroxybenzylideneamino)-2-hydroxymethylpropane-1,3-diol (HL) and 2-hydroxymethyl-2-(2-hydroxy-5-nitrobenzylideneamino)propane-1,3-diol (HL1) were determined. The resulting complexes were formulated as [Cu3OL3(H2O2]NO3 · 3H2O (I) and [Cu(H2O)L1]NO3 (II). The crystals of I are monoclinic, a = 17.809(4) Å, b = 30.549(6) Å, c = 18.962(4) Å, β = 115.36(3)°, space group Cc, Z = 8, R = 0.0482. Complex I is composed of two independent three-dimensional µ3-oxo complexes; the coordination polyhedron of the copper atoms in both compounds is an elongated tetragonal bipyramid. The coordination polyhedron of the third Cu atom is a tetragonal pyramid. The bases of the pyramids are composed of the oxygen atoms of the phenol and alcohol OH groups, the imine N atom of ligand L, and µ 3-oxo atoms. The phenol and water O atoms serve as the apices in both the tetragonal bipyramids. The crystals of II are triclinic, a = 6.062(1) Å, b = 7.701(2) Å, c = 16.162(3) Å, α = 88.15(3)°, β = 84.94(3)°, γ = 78.13(3)°, space group P1¯, Z = 2, R = 0.0272. Complex II is composed of polymer chains formed by coordination bonds between the copper atom and two O atoms of the amino alcohol in the azomethine of the neighboring complex connected to the initial one by translation along the x axis. These chains are linked through hydrogen bonds involving the oxygen atoms of the NO2 groups. The benzene rings of the azomethine ligands of the adjoining complexes from different chains are antiparallel to each other. The coordination polyhedron of the central atom is an elongated tetragonal bipyramid. Its equatorial plane is formed by the phenol O atom, one of the alcohol O atoms, the N atom of ligand L1, and the O atom of the amino alcohol in the neighboring complex. The apices are the O atom of the water molecule and the O atom of the amino alcohol in the neighboring azomethine molecule. In complexes I and II, the outer-sphere nitrato group mainly serves to unite trimers and polymers in the crystal by means of hydrogen bonds.__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 8, 2005, pp. 621–629.Original Russian Text Copyright © 2005 by Chumakov, Tsapkov, Simonov, Antosyak, Bocelli, Perrin, Starikova, Samus, Gulea. 相似文献
18.
Jian-Yong Zhang Yan-Qin Wang Hui-Qi Peng Ai-Ling Cheng En-Qing Gao 《Structural chemistry》2008,19(3):535-539
A new coordination polymer with interesting supramolecular architecture, [Zn(4-tzbz)]
n
(1) (4-tzbz = 4-(tetrazol-5-yl)benzoate), has been synthesized and characterized structurally. In this compound, the zinc(II)
ions are connected by the tetrazole ring in the μ2-1,4 bridging mode and the carboxylate group in the μ2-1,3 syn-anti bridging mode to generate 2D (4,4) sheets, and the adjacent sheets are linked further by the benzene rings to give the 3D
metal–organic framework with a 3,4-connected (83)(84122) topology. This compound in the solid state exhibits photoluminescence assignable to intraligand transitions, and, in particular,
the emission at 400 nm is significantly intensified due to the coordination of the ligand to Zn. 相似文献
19.
Abstract
Based on the polydentate ligand 3,5-bis(3-pyridyl)-1H-1,2,4-triazole (3,3′-Hbpt), three coordination compounds [Zn(3,3′-Hbpt)(ip)]·2H2O (1), [Zn(3,3′-Hbpt)(5-NO2-ip)]·H2O (2), and [Zn(3,3′-Hbpt)2(H2pm)(H2O)2]·2H2O (3) have been hydrothermally constructed with H2ip, 5-NO2-H2ip and H4pm as auxiliary ligands (H2ip = isophthalic acid, 5-NO2-H2ip = 5-NO2-isophthalic acid, H4pm = pyromellitic acid). Structural analysis reveals that Zn(II) ions serve as four-coordinated, five-coordinated, and six-coordinated connectors in 1–3, respectively, while 3,3′-Hbpt adopts μ-Npy and Npy coordination modes in two typical conformations in these target coordination compounds. Dependently the applied ligand, compounds 1–3 exhibit either 1D channel, cage or chain structures, respectively. In addition, the luminescence properties of 1–3 have been investigated in the solid state at room temperature. 相似文献20.
Three new zinc(II) complexes, Zn(L1)(NO3)2
(1), {[Zn(L1)(fumarate)]·2H2O}
n
(2) and {[Zn(L2)(fumarate)]·DMF}
n
(3) (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo [14,4,01.18,07.12]docosane) have been synthesized and characterized by analytical, spectroscopic, thermal and X-ray diffraction methods. The
structure of the discrete neutral complex (1) shows that the central zinc(II) ion is coordinated axially by two nitrate ligands. In the structures (2) and (3), the carboxylate groups of the bridging fumarate ligands are coordinated to zinc(II) macrocycles, resulting in the formation
of 1D coordination polymers. Apart from the fairly strong Zn–O bonds in (2) and (3), it is observed that the hydrogen bonds between the pre-organized N–H groups of the macrocycle and axial ligands appear to
be important for the design and development of metal complexes having a strong Zn–O bond. 相似文献