稀土-六氰合铁氰根桥联配合物的晶体结构和磁化学

以N,N'-二甲基乙酰胺为杂化配体,合成了稀土-铁氰根桥联配合物,测定了其中三个配合物的晶体结构和磁学性质,([SmFe)~n,Gd~2Fe,HoFe)。结果发现在相同的反应条件的一个系列中,呈现三种截然不同的晶体结构,分别为一维链状结构,三核结构和双核结构。同时发现这些配合物具有优良的磁化学性质,特别是[SmFe]~n呈现长程磁有序,临界温度(T~c=3.5K)和较大的矫顽力(H~c=1400Oe)。     

Charge transfer complexes of methylnaphthalene derivatives with TCNE in CCl4.

The spectrophotometric and thermodynamic properties of different substituted methylnaphthalenes charge transfer (CT) complexes with tetracyanoethylene have been studied in carbon tetrachloride. The spectral characteristics of the CT bands have also been discussed in relation to the positions of methyl groups. The formation constants and the spectral properties of the complexes are markedly affected with the substitution position of the methyl groups. The ionization potentials of the donors are determined.     

Theoretical studies of azapentalenes. Part 4: Theoretical study of the properties of 3a,6a-diazapentalene

A theoretical study of the properties of the isolated 3a,6a-diazapentalene by means of DFT, B3LYP/6-311++G(d,p) and ab initio methods, MP2/6-311++G(d,p), has been carried out. In addition, the complexes formed with hydrogen bond donor, acceptors, cations, and anions have been studied and analyzed. Ring opening into 1,5-diazocine as well as basicity and acidity properties of 3a,6a-diazapentalene have been explored. Their ability to form HB complexes and the complexes formed with anions and cations have been studied.     

Tetraanthraquinonoporphyrazines: III. Synthesis and physicochemical properties of metal complexes of hydroxy-substituted tetraanthraquinonoporphyrazines

Methods have been developed for the synthesis of metal complexes of hydroxy-substituted tetraanthraquinonoporphyrazines. The yield of the target products has been improved via complexation with the corresponding methoxy derivatives and subsequent hydrolysis of the methoxy groups. Some physicochemical properties of substituted 9,10-dioxo-9,10-dihydroanthracene-2,3-dicarboxylic acids and tetraanthraporphyrazine metal complexes derived therefrom have been studied.     

Binding at molecule/gold transport interfaces. V. Comparison of different metals and molecular bridges

The geometric and electronic structural properties of symmetric and asymmetric metal cluster-molecule-cluster' complexes have been explored. The metals include Au, Ag, Pd, and Al, and both benzenedithiol and the three isometric forms of dicyanobenzene are included as bridging molecules. Calculated properties such as cluster-molecule interface geometry, electronic state, degree of metal --> molecule charge transfer, metal-molecule mixing in the highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) energy region, the HOMO-LUMO gap, cluster --> cluster' charge transfer as a function of external field strength and direction, and the form of the potential profile across such complexes have been examined. Attempts are made to correlate charge transport with the characteristics of the cluster-complex systems. Indications of rectification in complexes that are asymmetric in the molecule, clusters, and molecule-cluster interfaces are discussed. The results obtained here are only suggestive because of the limitations of the cluster-complex model as it relates to charge transport.     

Chemistry of dithiocarbamate derivatives of amino acids. Part II. Complexes of nickel(II) with derivatives of branched and cyclic amino acids

Summary Barium salts of the dithiocarbamate derivates of the amino acids: DL-valine, L-valine, DL-leucine, DL-isoleucine and L-proline have been synthesized. The anions have been used to obtain the corresponding nickel(II) complexes in acid form. The complexes are diamagnetic, and coordination takes place in a near-square planar geometry around the nickel(II) ion through the sulphur atoms of the dithiocarbamate moiety, the structure being confirmed by i.r.,¹H n.m.r., u.v.-vis spectros copies and by chemical analysis.No significant difference has been found between the physicochemical properties (i.r. and 'H n.m.r. spectra and magnetic properties) of the complexes prepared from the dithiocarbamate derivatives of DL- and L-valine, but d-d bands in the u.v.-vis spectra show a slight different intensity.     

Enantioselective sensing of dicarboxylates. Influence of the stoichiometry of the complexes on the sensing mechanism

Two new cyclohexane-based thiourea chiral ligands have been synthesized in their enantiomerically pure forms. Both the ability of these ligands in the complexation of chiral dicarboxylates and their sensing properties have been studied. The influence of the stoichiometry of the formed complexes on the fluorescent properties of the systems has been established. The effect of additional substitution in the cyclohexyl moiety was considered by comparing the properties of the newly prepared ligands with those of similar compounds previously described.     

Semi-empirical molecular orbital calculations of the properties of 2:1 hydrogen bonded complexes of water with some ketones and ethers

The properties (molecular geometries and hydrogen bond energies) of a number of 2:1 complexes formed between water and some ketones and ethers have been calculated using both the CNDO/2 and the MINDO/3 semi-empirical molecular orbital methods. The CNDO/2 results have been compared with those obtained using the MINDO/3 method, and have been correlated with the i.r. spectroscopic properties of the complexes. The results for the 2:1 complexes have also been compared with those of 1:1 complexes formed with the same solvents.     

Synthesis, characterization and photochromic studies of spirooxazine-containing 2,2'-bipyridine ligands and their rhenium(I) tricarbonyl complexes

A series of spirooxazine-containing 2,2'-bipyridine ligands and their rhenium(i) tricarbonyl complexes has been designed and synthesized, and their photophysical, photochromic and electrochemical properties have been studied. The X-ray crystal structures of two of the complexes have been determined. Detailed studies showed that the emission properties of the complexes could readily be switched through photochromic reactions.     

Thiazolidine-4-carboxylic acid and 2-aminothiazoleethanoic acid as ligands. The synthesis, magnetic, e.p.r. and spectral properties of copper(II) complexes

Summary Two complexes formed from Cu^II acetate and thiazolidine-4-carboxylic acid (4-TCA) and 2-amino-4-thiazoleethanoic acid (ATAA) have been prepared and characterized by magnetic and spectroscopic techniques. The influence of the nature of ligands and solvents upon Cu^II e.p.r. properties was investigated for these compounds, Spin-Hamiltonian parameters from these data enabled suggestions concerning the structure of these complexes and the binding ability of the ligands.     

X-ray structural investigation of gossypol and its derivatives. X. Unusual inclusion compounds based on gossypol

More than 100 crystalline molecular complexes of gossypol with various organic molecules have been obtained and identified, and for 67 of them single crystals have been grown and their crystallographic parameters have been determined. On the basis of an interpretation of the structures of 30 complexes by the method of x-ray structural analysis, it has been shown that gossypol exhibits unusual including properties. Thus, in addition to all possible types of inclusion compounds this substance forms five polymorphic modifications, solvates, and a coordinoclathrate. The inclusion compounds of gossypol clearly distinguish polar guest molecules from nonpolar ones.A. S. Sadykov Institute of Bioorganic Chemistry, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 675–679, September–October, 1988.     

meso-四(对烷氧苯基)卟啉及其金属配合物的合成、表征及液 晶性

合成了meso-四(对烷氧苯基)卟啉及其Cu,Co,Zn,Pb金属配合物38个,其中14个为未见文献报道的新化合物。用元素分析,IR,UV,^1HNMR,MS对其进行了表征,确证了其结构。研究了这五个系列化合物的液晶性能,发现16个化合物具有液晶性,探讨了烷氧基链长及配位金属离子对液晶性能的影响。     

Spectroscopic,structure and DFT studies of palladium(II) complexes with pyridine-type ligands

Five palladium(II) complexes with pyridine derivative ligands have been synthesized. The molecular structures of the complexes were determined by X-ray crystallography, and their spectroscopic properties were studied. Based on the crystal structures, computational investigations were carried out in order to determine the electronic structures of the complexes. The electronic spectra were calculated with the use of time-dependent DFT methods, and the electronic spectra of the transitions were correlated with the molecular orbitals of the complexes. The emission properties of the complexes have been examined.     

Transition metal ion complexes of tiosemicarbazones derived from 2-acetylpyridine. Part 10. A comparison of the chemical and antifungal properties of the copper(II) complexes of 2-acetylpyridine 3-pyrrolidinyl-, 3-piperidinyl-, 3-hexamethyleneiminyl- and 3-azabicyclo[3,2,2]-nonylthiosemicarbazones

Summary Copper(II) complexes of the 3-pyrrolidinylthiosemicarbazones of 2-acetylpyridine and 2-acetylpyridineN-oxide have been prepared and their physical and spectral properties determined. Growth inhibition ofAspergillus niger, Paecilomyces variotii, Penicillium rubrum, andAspergillus terreus by thiosemicarbazones and their copper(II) complexes has been measured. These results are compared to 2-acetylpyridine 3-azacyclothiosemicarbazone ligand complexes.     

STUDY OF HETEROCYCLIC POLYMER COMPLEXES Ⅰ. POLYPHENYLQUINOXALINE-PLATINUM AND RHODIUM COMPLEXES*

Two new polyphenylquinoxaline-platinum and rhodium complexes were synthesized and iden-tified by X-ray photoelectron spectroscopy. Their catalytic properties on hydrosilylation and hy-drogenation of olefines have been investigated. It was found that these polymer complexes possessedhigh selective catalytic activities, and were easily recoverable after each reaction and could berepeatedly used for more than 10 times while maintaining the same effectiveness.     

Design, synthesis, characterization, luminescence and non-linear optical (NLO) properties of multinuclear platinum(II) alkynyl complexes

A series of luminescent multinuclear platinum(II) alkynyl complexes containing triethynylbenzene or 1,4-bis(3,5-diethynylphenyl)buta-1,3-diyne as cores has been successfully synthesized and characterized. The electronic absorption, emission, nanosecond transient absorption and electrochemical properties of these complexes have been reported. These complexes show long-lived emissions in degassed benzene solution and in alcoholic glass at 77 K. Moreover, they are found to exhibit two-photon absorption (2PA) and two-photon induced luminescence (TPIL) properties, and their two-photon absorption cross-sections have been determined to be 6-191 GM upon excitation at 720 nm. Through a systematic comparison, it has been found that tetra- and hexanuclear platinum(II) complexes show better 2PA and TPIL properties than their di- and trinuclear counterparts.     

Effect of constrained donor atom orientations on the stabilities, complexation kinetics, redox potentials, and structures of macrocyclic polythiaether Complexes. Copper(II) complexes with cyclopentanediyl derivatives of [14]aneS4 in 80% methanol

The two ethylene bridges in the macrocyclic tetrathiaether 1,4,8,11-tetrathiacyclotetradecane ([14]aneS(4)) have been systematically replaced by cis- or trans-1,2-cyclopentane to generate a series of new ligands that exhibit differing preferences for the orientation of the sulfur donor atoms while maintaining constant inductive effects. The resulting five dicyclopentanediyl derivatives, along with two previously synthesized monocyclopentanediyl analogues, have been complexed with Cu(II), and their stability constants, formation and dissociation rate constants, and redox potentials have been determined in 80% methanol/20% water (by weight). The crystal structures of the Cu(II) complexes with the five dicyclopentanediyl-[14]aneS(4) diastereomers as well as the structures for a representative Cu(I) complex and one of the free ligands have also been determined. The properties of these complexes are compared to previous data obtained for the corresponding cyclohexanediyl derivatives in an attempt to shed additional light on the influence of sterically constraining substituents upon the properties of macrocyclic ligand complexes.     

Non-covalent polymerisation in the solid state: halogen-halogen vs. methyl-methyl interactions in the complexes of 2,4-di(2-pyridyl)-1,3,5-triazine ligands

Fe(II), Co(II), Ni(II) and Cu(II) complexes based on the triazine ligand 2,4-di(2'-pyridyl)-6-(p-bromo-phenyl)-1,3,5-triazine have been synthesised and characterised. The electrochemical, magnetic and spectroscopic properties of the complexes have also been investigated, and the electron deficient triazine ligand has been shown to affect each of these properties. Further investigation of solid state structures of the ligand and its Fe(II), Co(II) and Cu(II) complexes has established that stabilising Br-Br interactions exist which link neighbouring molecules to form one-dimensional tapes. A slight modification of the ligand, i.e., using 2,4-di(2'-pyridyl)-6-(p-methylphenyl)-1,3,5-triazine, in which the phenyl substituent has changed from a bromine to a methyl group, eliminates the one-dimensional tape and gives rise to significant pi-stacking interactions in the solid state.     

Novel copper(II) homobinuclear macrocyclic complexes: cyclic voltammetry, biological properties and spectral studies

A series of five new copper(II) macrocyclic complexes have been synthesized by template condensation. The bonding and stereochemistry of the complexes have been characterized by elemental analysis, molar conductance, magnetic susceptibility, IR, UV-visible, EPR spectral studies and electrochemical properties. g-Values are calculated for all of the complexes in polycrystalline form as well as in DMSO solution. The magnetic and spectral data indicate square planar geometry for all the complexes. Cyclic voltammograms for all the complexes are similar and involve two quasi-reversible redox processes. Cu(II)Cu(II)<=>Cu(II)Cu(I)<=>Cu(I)Cu(I). Their biological properties have also been studied. The macrocyclic complexes show more anti-bacterial than controlled one. The anti-bacterial activities of the compounds were tested against Streptococcus fecalis and Escherichia coli with different concentrations.     

Antibacterial,antioxidant and anthelmintic studies of inclusion complexes of some 4-arylidenamino-5-phenyl-4H-1,2,4-triazole-3-thiols

A series of 4-arylidenamino-5-phenyl-4H-1,2,4-triazole-3-thiols have been synthesised and their inclusion complexes have been prepared with β-cyclodextrin. The compounds and their inclusion complexes have been characterised by studying their physical and spectral properties. The thermodynamic stability constant and free energy of activation have been determined to know the stability of inclusion complexes. Finally, the compounds and their inclusion complexes are screened for antibacterial, antioxidant and anthelmintic activities. It is found that inclusion complexes of the newly synthesised compounds have appreciable stability and inclusion complex formation increases the antibacterial, antioxidant and anthelmintic activities significantly as compared to naked compound.