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1.
Boris‐Marko Kukovec Zora Popovi Gordana Pavlovi 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(9):m389-m391
In the title compound, [Cd(C7H6NO2)2]n, the CdII ion has a distorted octahedral geometry. The 6‐methylpyridine‐2‐carboxylate anions are perpendicular to one another and act as bidentate and bridging ligands. Two carboxylate O atoms bridge the CdII ions, forming centrosymmetric dinuclear units. These units are further connected via carboxylate O atoms into a one‐dimensional polymeric chain which extends in the [100] direction. 相似文献
2.
Neven Smrečki Boris-Marko Kukovec Igor Rončević Zora Popović 《Structural chemistry》2018,29(1):195-206
The reactions of N-alkyliminodiacetamide derivatives, namely N-ethyliminodiacetamide (CH3CH2N(CH2CONH2)2; Etimda) and N-isopropyliminodiacetamide (CH3)2CHN(CH2CONH2)2; i-Primda), with sodium tetrachloropalladate(II) in aqueous solutions were investigated. Three new palladium(II) complexes, [Pd(Etimda?H)2]?2H2O (1), [Pd(i-Primda?H)2]?2H2O (2) and [PdCl2(i-Primda)] (3), were obtained and characterized by X-ray structural analysis, infrared spectroscopy and thermal analysis (TGA). The square planar coordination environments around the palladium(II) ions in complexes 1 and 2 consist of two N,N′-bidentate N-alkyliminodiacetamidato ligands, with imino N atoms in trans-position. The complex 3 also exhibits a square planar coordination environment around Pd(II), but with two chloride ions and one neutral N-isopropyliminodiacetamide ligand bound in an N,O′-bidentate coordination mode. The described coordination modes, as well as the presence of deprotonated amide groups in ligands in 1 and 2, are found for the first time in palladium(II) complexes with iminodiacetamide type ligands. The molecular geometries and infrared spectra of these three complexes were also modelled using DFT calculations, at the BP86-D3/def2-TZVPP/PCM level of theory. The RMSD values suggest a good agreement of the calculated and experimental geometries. A QTAIM analysis suggests a qualitative correlation between bond lengths and energy densities, also supported by an NBO analysis. The dimer interaction energy between complex units was estimated at about ?15 kcal/mol for all complexes. 相似文献
3.
Boris-Marko Kukovec Zora Popović Gordana Pavlović Marijana Vinković Dražen Vikić-Topić 《Polyhedron》2008
Cadmium(II) complexes of 3-hydroxypicolinic acid, namely [CdI(3-OHpic)(3-OHpicH)(H2O)]2 (1), [Cd(3-OHpic)2(H2O)2] (2) and [Cd(3-OHpic)2]n (3) were prepared and characterized by spectroscopic methods (IR, NMR) and their molecular and crystal structures were determined by X-ray crystal structure analysis. Complexes 1 and 2 were prepared in similar reaction conditions using different cadmium(II) salts: cadmium(II) iodide and cadmium(II) acetate dihydrate, respectively, while 3 was prepared by recrystallization of 2 from N,N-dimethylformamide solution. Various coordination modes of 3-OHpicH in 1–3 were established in the solid state: bidentate N,O-chelated mode in 1 and 2, monodentate mode through the carboxylate O atom from zwitterionic ligand in 1 and bidentate N,O-chelated and bridging mode in 3. In the DMF solution of all prepared complexes, only monodentate mode of 3-OHpicH binding to cadmium(II) through the carboxylate O atom was established by 1H, 13C, 15N and 113Cd NMR spectroscopy. 相似文献
4.
Mohammad Hakimi Boris-Marko Kukovec Mao Minoura 《Journal of chemical crystallography》2012,42(3):290-294
Abstract
The reaction of pyridine-2,6-dicarboxylic acid (dipicolinic acid, dipicH2) with potassium tetraperoxochromate(V) in the mixture of water and ethanol led to the formation of a 2D s-d mixed-metal coordination polymer of {K[Cr(dipic)2]}n (1). The compound was characterized by spectroscopic methods (IR, Raman, UV/Vis). Single crystal X-ray diffraction analysis revealed that dipicolinate ligand is coordinated to the chromium(III) ion in an O,N,O′-tridentate fashion, while its uncoordinated and coordinated carboxylate O atoms (with respect to Cr(III) ion) are in turn bound to potassium ions. Therefore, each dipicolinate ligand bridges two potassium ions and a chromium(III) ion between them, giving rise to a 2D coordination network. The coordination of chromium(III) ions is octahedral, while the coordination number of potassium ions is 8. The coordination networks are in turn assembled only by π–π stacking interactions into a 3D structure. 相似文献5.
Zora Popovi Gordana Pavlovi Boris‐Marko Kukovec 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(5):m181-m183
The title compound, [Cu(C9H5N2O3)2(C2H6OS)2], consists of octahedrally coordinated CuII ions, with the 3‐oxo‐3,4‐dihydroquinoxaline‐2‐carboxylate ligands acting in a bidentate manner [Cu—O = 1.9116 (14) Å and Cu—N = 2.1191 (16) Å] and a dimethyl sulfoxide (DMSO) molecule coordinated axially via the O atom [Cu—O = 2.336 (5) and 2.418 (7) Å for the major and minor disorder components, respectively]. The whole DMSO molecule exhibits positional disorder [0.62 (1):0.38 (1)]. The octahedron around the CuII atom, which lies on an inversion centre, is elongated in the axial direction, exhibiting a Jahn–Teller effect. The ligand exhibits tautomerization by H‐atom transfer from the hydroxyl group at position 3 to the N atom at position 4 of the quinoxaline ring of the ligand. The complex molecules are linked through an intermolecular N—H...O hydrogen bond [N...O = 2.838 (2) Å] formed between the quinoxaline NH group and a carboxylate O atom, and by a weak intermolecular C—H...O hydrogen bond [3.392 (11) Å] formed between a carboxylate O atom and a methyl C atom of the DMSO ligand. There is a weak intramolecular C—H...O hydrogen bond [3.065 (3) Å] formed between a benzene CH group and a carboxylate O atom. 相似文献
6.
Copper(II) complexes of 6-methylpicolinic (6-MepicH) and 6-bromopicolinic acid (6-BrpicH), namely [Cu(6-Mepic)2(H2O)] (1), [Cu(6-Mepic)2(py)] (2) and [Cu(6-Brpic)2(H2O)] (3) were prepared and characterized by spectroscopic methods (IR, EPR). Their molecular and crystal structures were determined by X-ray crystal structure analysis, their thermal stability by TGA/DTA methods, while their magnetic properties were elucidated by the measurement of the magnetic susceptibility. X-ray structural analysis revealed an intermediate between square-pyramidal and trigonal-bipyramidal coordination polyhedron in 1 and 3 and a trigonal-bipyramidal one in 2 with the same N,O-chelated coordination mode for both 6-MepicH and 6-BrpicH in 1–3. EPR spectra showed three different types of copper(II) S = ½ symmetry signals. Most probably they could be assigned to the elongated axial in 1, the isotropic in 2 and the rhombic in 3. Both 1 and 2 showed the paramagnetic behaviour, while 3 exhibited an antiferromagnetic interaction, ascribed to the formation of pseudobinuclear units by the π···π stacking between pyridine rings. 相似文献
7.
Mohammad Hakimi Boris-Marko Kukovec Esther Schuh Zaynab Normohammadzadeh Fabian Mohr 《Journal of chemical crystallography》2012,42(2):180-185
Abstract
The reaction of propane-1,2-diamine (pdam) with lead (II) nitrate in the ethanol solution led to the formation of a lead (II) complex, [Pb(NO3)(pdam)2]NO3 (1), with interesting coordination environment of the lead (II) ion. The compound was characterized by elemental analysis and IR spectroscopy and its crystal structure was determined by single crystal X-ray structural analysis. Lead (II) ion is coordinated by two neutral N,N′-bidentate propane-1,2-diamine ligands and by an O,O′-bidentate nitrate ion in a complex cation of 1. There is also an uncoordinated nitrate ion as counter-ion. The primary coordination sphere around lead (II) ion includes four N atoms (Pb–N, 2.377(4)–2.644(4) ?). The effective coordination around lead (II) ion could be described as a highly distorted octahedron if the Pb···O contacts (Pb1···O4, 3.090(4) ?, Pb1···O5, 3.177(3) ?) are included. The coordination polyhedron is better described as a distorted pentagonal pyramid due to the presence of stereochemically active lead (II) ion lone pair of electrons in the axial position of the pyramid. Thus, the complex is hemidirected. Complex cations and nitrate counter-ions are connected into 3D structure by hydrogen bonds of the N–H···O type. 相似文献8.
Mohammad Hakimi Boris-Marko Kukovec Heidar Raissi Leila Pouyanmehr Fabian Mohr Esther Schuh 《Structural chemistry》2013,24(1):81-88
The symmetrical amino alcohol synthesis via ring opening of cyclohexene oxide with ethylendiamine is illustrated by synthesis and characterization of β-amino alcohols s-cis-(SSSS)-cy2en (1) and s-trans-(SSRR)-cy2en (2) (cy2en = N,N′-bis(2-hydroxycyclohexyl)ethane-1,2-diamine) in one step and with high yield. The reaction was carried out in a microwave reactor under solvent-free conditions. These products were characterized by IR and Raman spectroscopy, elemental analysis, thermal methods (TGA, DTG and DTA), mass spectrometry and 1H and 13C NMR spectroscopy. The crystal structures of 1 and 2 were determined by single crystal X-ray structural analysis, followed by DFT calculations. Intramolecular hydrogen bond was observed in 1 with C 2 symmetry, but not in 2 with C i symmetry. The nature of intramolecular hydrogen bond in 1 has been investigated by AIM and NBO analyses. The molecules in 1 are linked into an infinite chain along the [001] direction, giving rise to R 4 4 (8) graph-set motif, while the molecules in 2 are linked into a 2D network in the bc plane, giving rise to R 2 2 (10) and R 3 3 (12) motifs. The protonation equilibria of 1 and 2 have been studied by pH-potentiometry, with pK 1 9.01 and pK 2 5.50 determined for 1 and pK 1 8.58 and pK 2 5.26 determined for 2. 相似文献
9.
Treatment of a neutral aqueous solution of dipicolinic acid (dipicH2), 3-amino-1H-1,2,4-triazole (atr) and CrCl3·6H2O in the presence of AgNO3 (in molar ratio 1:1:1:3) under hydrothermal condition led to the formation of a co-crystal of {[Ag(atr)2][Cr(dipic)2]}2·[Cr(H2O)(dipic)(μ-OH)]2·4H2O (1). Compound 1 was characterized by elemental analyses, IR and UV-Vis spectroscopy as well as X-ray diffraction studies. The structure consists of two [Ag(atr)2]+ cations, two [Cr(dipic)2]− anions, one co-crystallized neutral dinuclear chromium(III) complex, [Cr(H2O)(dipic)(μ-OH)]2, and four co-crystallized water molecules. Silver(I) ion in [Ag(atr)2]+ is coordinated by two monodentate 3-amino-1H-1,2,4-triazole ligands, bound via endocyclic nitrogen atoms, in a linear fashion. Chromium(III) ion is octahedrally coordinated by two O,N,O-tridentate dipicolinate ligands in anionic complex. Each chromium(III) ion in neutral dinuclear complex, [Cr(H2O)(dipic)(μ-OH)]2, is octahedrally coordinated by one O,N,O-tridentate dipicolinate ligand, one water molecule and two bridging μ-OH ions in cis position. Thermal methods (TGA/DTA) confirm the number of co-crystallized water molecules in 1. 相似文献
10.