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61.
Farzin Marandi Dr. Babak Mirtamizdoust Suchada Chantrapromma Hoong‐Kun Fun 《无机化学与普通化学杂志》2007,633(9):1329-1332
A 2D lead(II) coordination polymer [Pb2(phen)2(N3)3(ClO4)]n,( 1 ) containing 1,10‐phenanthroline (phen) and two different anions, has been synthesized and characterized by elemental analysis, IR and 1H NMR spectroscopy and X‐ray crystallography. The single‐crystal X‐ray data show two different kinds of Pb2+ ions with coordination numbers of eight, Pb1 = PbN6O2 and Pb2 = PbN8, with hemidirected and holodirected structures, respectively. The supramolecular features in 1 is negiotated through the weak but directional C‐H···O and C‐H···N interactions and aromatic π–π stacking interactions. 相似文献
62.
Rudi van Eldik 《Angewandte Chemie (International ed. in English)》1986,25(8):673-682
In order to understand the dynamics of chemical reactions in general, detailed information on electronic, structural and kinetic properties is required. The key questions on how chemical reactions actually occur can in many cases only be answered in terms of information obtained from kinetic studies. In conventional kinetic studies of chemical reactions in solution, the variables usually selected include concentration, acidity, solvent, and temperature. In recent years, pressure has become an additional selected variable in such studies. It enables the measurement of the volume of activation and the construction of reaction volume profiles and thus assists in the elucidation of the underlying mechanism; it also completes the comprehension of reaction kinetics by adding another kinetic parameter that the suggested reaction mechanism must account for. Furthermore, the volume of activation is the only transition state property that can be correlated with the corresponding ground state property in an experimentally simple manner. In this paper, the insights so gained in our understanding of the dynamics of reactions involving coordination complexes will be presented. Such reactions are of fundamental interest to chemists since they often form the basis of catalytic, biological, environmental and energy related processes. Any additional information that will add to the understanding of the reaction dynamics is therefore of exceptional importance. 相似文献
63.
64.
A new mercury(II) complex of 1,2‐bis(4‐pyridyle)ethene (bpe) with anionic acetate and thiocyanate ligands has been synthesized and characterized by elemental analysis, IR, 1H NMR and 13C NMR spectroscopy. The single crystal X‐ray analysis shows that the complex is a two‐dimensional polymer with simultaneously bridging 1,2‐bis(4‐pyridyle)ethane, acetate and thiocyanate ligands and basic repeating dimeric [Hg2(μ‐bpe)(μ‐OAc)2(μ‐SCN)2] units. The two‐dimensional system forms a three‐dimensional network by packing via π‐π stacking interactions. 相似文献
65.
E. Bernhardt 《Journal of fluorine chemistry》2004,125(6):967-973
First examples for the syntheses of trifluoromethyl transition metal complexes by conversion of a cyano into a trifluoromethyl ligand are described. The fluorination of [][Au(CN)4] with ClF in CH2Cl2 leads to the formation of a mixture of gold complexes of the type [AuFxCly(CF3)4−x−y]− (x=0-4, y=0-2). Ligand exchange reactions of [AuFxCly(CF3)4−x−y]− (x=0-4, y=0-2) with (CH3)3SiY (Y=Cl, CN) are performed resulting in anions of the type [AuYx(CF3)4−x]− (x=0-4). All products are characterised by - and NMR spectroscopy. 相似文献
66.
A new one-dimensional copper coordination polymer chain has been prepared and fully characterized by single-crystal X-ray diffraction,elemental analyses and IR spectroscopy. The compound {[Cu2(C2O4)2(inta)4](inta)}n1 crystallizes in the triclinic system,space group P1,with a=8.4722(5),b=10.9825(6),c=11.6128(6),α=104.8050(10),β=102.5740(10),γ= 109.6890(10)o,V=927.18(9)3,Mr=929.79,Z=1,Dc=1.665 g/cm3,F(000)=475,μ=1.231 mm-1,R=0.0453 and wR=0.1185 for 3290 observed reflections (I > 2σ(I)). Of the compound,the Cu center is octahedrally coordinated with oxalate acting as a tetra-dentate ligand coordinated to the copper atom and each inta serving as a terminal ligand by employing only one N-donor to coordinate with the Cu center. An infinite {Cu2(C2O4)2}∞ chain is formed along the c axis. Furthermore,the 1D chains are held together via extensive hydrogen-bonding interactions to generate a three-dimensional network with 1D channels (ca. 5.491×11.507) where inta molecules are filled. 相似文献
67.
Cyanide Bridged Coordination Polymers from cis‐ or trans‐[Ru(tBuNC)4(CN)2] and MnCl2: About the Influence of Different Topologies on the Magnetic Properties of Materials The reaction of cis‐ or trans‐[Ru(tBuNC)4(CN)2] with MnCl2 as an additional transition metal fragment yields the one dimensional coordination polymers {cis‐[Ru(CN)2(tBuNC)4] MnCl2}n, ( 1 ), and {trans‐[Ru(CN)2(tBuNC)4]MnCl2}n, ( 2 ), with a different arrangement of the metal centers caused by the different stereochemistry of the starting compounds. The variation of the Ru‐C‐N‐Mn geometry nevertheless leads to significant differences in the magnetic properties of 1 and 2 . The coordination polymer derived from trans‐[Ru(tBuNC)4(CN)2] shows a more efficient antiferromagnetic intrachain interaction between the manganese centers compared to the cis‐derivative. 相似文献
68.
Acrylamide complexes of metal nitrates: [M(O‐OC(NH2)CHCH2)n(H2O)m][NO3]2 (M = Co( 1 ), Ni( 2 ) (n = 6 and m = 0) and Zn( 3 ) (n = 4 and m = 2)) have been determined by using single crystal X‐ray diffraction analysis. All complexes crystallize in the triclinic space group . The structures of 1 and 2 represent octahedral species [M(AAm)6]2+ (AAm = O‐OC(NH2)CHCH2 and M = Co or Ni) and uncoordinated nitrate ions. The structure of 3 involves the octahedral cation [Zn(AAm)4(H2O)2]2+ in which the Zn2+ environment includes oxygen atoms of four acrylamide and two water molecules that are stabilized using ionic nitrate ions. The observations of the solid‐state IR spectroscopic vibrational frequencies of these acrylamide complexes are in agreement with the crystal structures. 相似文献
69.
The enthalpy changes, entropy changes and equilibrium constants of coordination reactions of 18-crown-6 with the alkali ions Na+ and K+ at 298.15K were measured by using RD-496 microcalorimeter with methanol, ethanol, n-propanol and n-butanol as solvents respectively. The results indicated that the enthalpy changes △rHm, entropy changes △rSm, and the stability of the complexes are closely related with the polarity of the solvents, and the order of the stability is ethanol>methanol>n-propanol>n-butanol>H2O for the same complex in the solvents investigated. The stability order was reasonably explained by relating the stability constants of the complexes with the dielectric constants of these solvents, and by using the model of solvated-desolvated ions and ion pair in the coordination reactions. 相似文献
70.
Structural tuning of coordination polymers by 4-connecting metal node and secondary building process
Due to variation in ligand's conformation, metal node's connecting geometry, and secondary building process by anions, bat-like, dumbell-like, diamondoid, or pillar-layer topologies are achieved. 相似文献