bluuebunny/crossref_metadata_2025 huggingface dataset:
Oral hypoglycaemic activity of Ipomoea aquatica in streptozotocin‐induced, diabetic wistar rats and Type II diabetics
Authors: Malalavidhane T. S. , Wickramasinghe S. M. D. N. , Perera M. S. A. , Jansz E. R.
Published: October 2003

Ipomoea aquatica Forsk is a common green leafy vegetable consumed in many parts of the world. The present study was designed to investigate the oral hypoglycaemic activity of Ipomea aquatica in streptozotocin induced diabetic Wistar rats, and Type II diabetic patients. Experimental diabetes was induced with streptozotocin in Wistar rats. The rats were then divided into test and control groups. In addition to the standard feed given to both groups the test was fed with the shredded leaves of Ipomoea aquatica (3.4 g/kg) for one week. Type II diabetic patients were subjected to a glucose challenge before and after a single dose of blended I. aquatica. Patients acted as their own controls. The results revealed that consumption of the shredded, fresh, edible portion of I. aquatica for one week, effectively reduced the fasting blood sugar level of streptozotocin‐induced diabetic rats (p = 0.01). When subjected to a glucose challenge, the Type II diabetic subjects showed a signiﬁcant reduction (p = 0.001) in the serum glucose concentration 2 h after the glucose load. However, it was not signiﬁcantly reduced at 1 h (p < 0.09) post glucose load. There was a 29.4% decrease in the serum glucose concentration of the diabetic patients when treated with the plant extract. Copyright © 2003 John Wiley & Sons, Ltd.
Plants used in cosmetics
Authors: Aburjai Talal , Natsheh Feda M.
Published: October 2003

This review describes the use of some natural products in cosmetic preparations, due to their low mammalian toxicity, with a brief description of the major use, plant parts used, the actives responsible for effect and the beneﬁts of such products. Their use in skin care; such as dryness, eczema, acne, free‐radical scavenging, antiinﬂammatory, antiaging and skin protection effects are explained, and also the use in hair care as hair growth stimulants, hair colorants, and for hair and scalp complaints such as dandruff. Essential oils when incorporated into ﬁnished products impart many beneﬁts such as a pleasant aroma in perfumery, shine or conditioning effects in hair care products, emolliency and improving the elasticity of the skin. Copyright © 2003 John Wiley & Sons, Ltd.
Screening South Indian medicinal plants for antifungal activity against cutaneous pathogens
Authors: Vonshak A. , Barazani O. , Sathiyamoorthy P. , Shalev R. , Vardy D. , Golan‐Goldhirsh A.
Published: October 2003

In this study, twenty‐eight South Indian medicinal plants were screened for their anti‐fungal activity against six species of fungi (Trichophyton mentagrophytes, T. rubrum, T. soudanense, Candida albicans, Torulopsis glabrata, and C. krusei). Three plant species extracts, Celastrus paniculatus, Eriodendron anfractuosum and Ficus glomerata showed inhibitory activity. An aqueous extract of galls of Terminalia chebula showed inhibitory effects on three dermatophytes (Trichophyton spp.) and three yeasts (Candida spp.). Seeds extract of T. chebula inhibited only the growth of T. glabrata. An aqueous extract of T. chebula showed inhibitory effects higher than those measured in ethanol extracts. It is therefore suggested that tannins are plausible candidates for the anti‐dermatophytic effects of T. chebula. Chebulinic acid, a known tannin of T. chebula was tested and found not inhibitory, thus a search for the active compound is needed. Copyright © 2003 John Wiley & Sons, Ltd.
Testing theory beyond molecular structure: Electron density distributions of complex molecules
Authors: Schiøtt B. , Overgaard J. , Larsen F. K. , Iversen B. B.
Published: October 2003

The electron density distribution (EDD) of a molecular system can be determined experimentally from elaborate X‐ray diffraction measurements or calculated with quantum mechanical methods: This provides a unique opportunity for mutual validation of the experimental and theoretical methods—a validation that goes far beyond comparison of molecular structures. Two examples of complex molecular systems of biologic relevance are presented. The first is the cocrystallized complex of betaine, imidazole, and picric acid, 1, which is a 75‐atom molecular complex serving as a model for the active site in the serine proteases class of enzymes, the so‐called catalytic triad. For 1 the experimental charge density was determined by combined modeling of single crystal synchrotron X‐ray and neutron diffraction data measured at 28(1) K, and it is compared with ab initio theoretical calculations at the B3LYP/6‐311G(d,p) level of theory. Overall, the agreement is good, but in one strong NHO hydrogen bond clear differences are observed. The second example concerns the EDD of the mixed valence trinuclear oxo‐centered iron carboxylate, [Fe3O(OOCC(CH3)3)6(NC5H5)3], 2. This molecule contains 133 atoms (542 electrons) including three open‐shell iron atoms, and the experimental investigation is based on synchrotron X‐ray diffraction data. Calculations in the experimental geometry at the commonly used UB3LYP/LanL2DZ level of theory are not able to reproduce a number of experimentally observed electron density features. In particular, thesp3‐like distribution on the central oxygen atom and the electron deformations on the iron centers are at variance with experiment. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Optimal robust disturbance attenuation for continuous time‐varying systems
Authors: Djouadi Seddik M.
Published: October 2003

In this paper we consider the Optimal robust disturbance attenuation problem (ORDAP) for continuous time‐varying systems subject to time‐varying unstructured uncertainty. We show that for causal (possibly time‐varying) continuous systems, ORDAP is equivalent to finding the smallest fixed point of a ‘two‐disc’ type optimization problem under time‐varying feedback control laws. Duality is applied in the context of nest algebra of causal stable systems, to prove existence of optimal continuous time‐varying controllers. We also show that for time‐invariant nominal plants, time‐varying control laws offer no improvement over time‐invariant feedback control laws. Copyright © 2003 John Wiley & Sons, Ltd.
LMI based stability analysis and robust controller design for discrete linear repetitive processes
Authors: Galkowski K. , Lam J. , Rogers E. , Xu S. , Sulikowski B. , Paszke W. , Owens D.H.
Published: October 2003

Discrete linear repetitive processes are a distinct class of 2D linear systems with applications in areas ranging from long‐wall coal cutting through to iterative learning control schemes. The main feature which makes them distinct from other classes of 2D linear systems is that information propagation in one of the two independent directions only occurs over a finite duration. This, in turn, means that a distinct systems theory must be developed for them. In this paper, the major new development is that an LMI based re‐formulation of the stability conditions can used to enable the design of a family of control laws which have a well defined physical basis. It is also noted that this setting can be used to investigate robustness aspects. Copyright © 2003 John Wiley & Sons, Ltd.
Apoptosis antagonizing transcription factor AATF is a novel coactivator of nuclear hormone receptors
Authors: Leister Peter , Burgdorf Sven , Scheidtmann Karl Heinz
Published: October 2003

Apoptosis antagonizing transcription factor AATF was identified as interaction partner of Dlk/ZIP kinase and shown to exhibit transactivation activity in Gal4‐based reporter gene expression assays. The human ortholog Che‐1 was independently isolated as interacting protein of RNA polymerase II suggesting that AATF might be a transcriptional adapter or mediator which serves to link transcriptional activators to the general transcription machinery. Consistent with this assumption, AATF contains several interaction motifs including a leucine zipper and three putative binding motifs for nuclear hormone receptors. In this study, we investigated a possible functional relationship of AATF to nuclear receptors. Indeed, AATF enhanced transactivation by several steroid hormone receptors including androgen, estrogen and glucocorticoid receptors in a hormone‐dependent manner. This enhancing effect was further increased by p300 but not by a mutant of p300 lacking acetyl transferase activity. AATF bound directly to the receptors in vitro. Co‐activation was impaired with AATF mutants bearing mutations in the LXXLL NR binding motifs. Our data suggest that AATF is a novel coactivator of nuclear hormone receptors.
Effects of estrogen on cell cycle progression and associated metabolic pathways in normal and tumorigenic breast cells
Authors: Hass Ralf , Sohn Christof
Published: October 2003

Estrogens are widely used in hormone replacement therapies but their actions particularly in combination with other hormones are poorly understood. Incubation of human MCF‐7 breast cancer cells with high doses of 17β‐estradiol demonstrated changes in morphology such as detachment of the adherent population and an accumulation in G2/M phase of the cell cycle within 24 h. Continuous treatment of MCF‐7 cells with up to 10 μM 17β‐estradiol every 24 h was also associated with the appearance of about 20% cell death in subG1 phase. Interestingly, MCF‐7 cells in G2/M phase following continuous incubation with 10 nM to 1 μM 17β‐estradiol returned to control cell cycle distributions with no significant cell death in subG1 after 96 h, respectively. These findings suggested an estrogen concentration‐dependent sensitivity of MCF‐7 cells. In contrast, incubation of normal human breast epithelial cells (HMEC‐1) with similar amounts of 17β‐estradiol did not result in any significant change in morphology and G2/M phase distribution, respectively, and continuous exposure of HMEC‐1 with up to 10 μM 17β‐estradiol demonstrated less than 5% of apoptotic subG1 populations. Investigations of short term signals revealed a significantly increased 20S proteasomal proteolytic activity which was dependent on poly(ADP‐ribose)polymerase in estrogen‐stimulated MCF‐7 tumor cells within 60 min. In contrast, there was little if any detectable change in this proteolytic activity in HMEC‐1 following estrogen treatment. Moreover, while expression levels of manganese superoxide dismutase and the matrix metalloproteinase MMP‐9 remained unchanged in MCF‐7 cells and HMEC‐1 during estrogen treatment, respectively, the amount of MMP‐1 and MMP‐7 significantly increased in the MCF‐7 tumor cells within 60 min after estrogen exposure. In contrast, MMP‐7 protein expression was progressively reduced in HMEC‐1 in an estrogen concentration‐dependent manner within 60 min. Taken together, these findings suggest different estrogen‐mediated signaling mechanisms in normal human breast epithelial cells when compared to their tumorigenic counterparts. Consequently, the distinct threshold effects of estrogen in vitro allow a certain signaling selectivity and may thus question the significance of an overall standard dose used in hormone replacement therapy.
The Fas ligand as a cell death factor and signal transducer
Authors: Linkermann Andreas , Qian Jing , Kabelitz Dieter , Janssen Ottmar
Published: October 2003

Fas ligand (FasL, CD95L) is the key death factor of receptor‐triggered programmed cell death in immune cells. FasL/Fas‐dependent apoptosis plays a pivotal role in activation‐induced cell death, termination of immune responses, elimination of autoreactive cells, cytotoxic effector function of T and NK cells and the establishment of immune privilege. Dysregulation of FasL‐expression has severe impact on the maintenance of immune homeostasis and defense and is often associated with pathophysiology. Moreover, it was recently shown that FasL serves as a costimulatory receptor during T cell activation. However, it is still not known whether FasL‐ligation induces a ‘direct’ signal or whether the regulation of activation signals is a more ‘indirect’ result of alterations in intracellular protein‐protein‐interactions. In the latter scenario, the proline rich domain of FasL was shown to be required for a directed transport and localization of FasL. Over the past years, potential FasL‐associating molecules were identified which mostly bind via Src homology 3 or WW domains to the proline rich domain of FasL. This review summarizes facts and hypotheses about these FasL‐interacting proteins. It reflects their potential role in reverse signal transduction and FasL biology in T lymphocytes and other cell types.
Interleukin‐4‐ and Interleukin‐13 receptors trigger distinct JAK/STAT activation patterns in mouse lymphocytes
Authors: Friedrich Karlheinz , Brändlein Stephanie , Ehrhardt Ingrid , Krause Sebastian , Luttmann Werner
Published: October 2003

Interleukin‐13 (IL‐13) is a T‐cell‐derived cytokine closely related to IL‐4 and functions as a central mediator of allergic asthma. The basis of overlapping activities of the two cytokines is the utilization of a common receptor subunit, the interleukin‐4 receptor α chain (IL‐4Rα). We addressed the signaling specificity of IL‐4 versus IL‐13, which rests on specific components of the respective receptor systems, i.e. the common γ chain (γc) for the IL‐4 receptor and the IL‐13 receptor α1 chain for the IL‐13 receptor. Hybrid receptors were engineered such that the consequences of intracellular pairing between IL‐4Rα and its two different dimerization partners could be directly compared in a background‐free fashion in mouse pro‐B cells. Experimentally induced dimers of both the IL‐4Rα/γc and the IL‐4Rα/IL‐13Rα1 type were capable of mediating a proliferative response and triggering STAT6 activity. Other JAK/STAT reactions, however, appeared characteristically distinct in the two systems. The IL‐4 receptor, upon activation, drove tyrosine phosphorylation of JAK1 and JAK3, whereas the IL‐13 receptor did not activate JAK3. Notably, only the IL‐4‐ but not the IL‐13 receptor was competent to evoke DNA‐binding activity of STAT5.
Synthesis of marine guanidine alkaloids and their application as chemical/biological tools
Authors: Nagasawa Kazuo , Hashimoto Yuichi
Published: October 2003

Ptilomycalin A and crambescidins, novel marine guanidine alkaloids, have a unique pentacyclic guanidine structure, and exhibit a considerable array of biological activities. The first method developed for the synthesis of the pentacyclic guanidine core structure involved successive 1,3‐dipolar cycloaddition reactions and resulted in the first total synthesis of crambescidin 359. The synthesis of other pentacyclic guanidine derivatives has been based on this methodology and applied as tools for studying biological activities, and as chemical reaction catalysts. © 2003 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 3: 201–211; 2003: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.10064
Organic supramolecular architectures and their sol‐gel transcription to Silica nanotubes
Authors: Jung Jong Hwa , Shinkai Seiji , Shimizu Toshimi
Published: October 2003

The design of artificial models of “biomineralization” processes that utilize sol‐gel polymerization has led to a merging of inorganic materials research and supramolecular organic chemistry. This article introduces self‐assembled superstructures of sugar‐integrated and crown‐appended cholesterol gelators, which are used as versatile building blocks in organogels and as templates for sol‐gel transcription. This article focuses on the use of self‐assembled organic superstructures in the creation of novel inorganic materials with controlled morphologies. © 2003 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 3: 212–224; 2003: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.10065
Elemental composition of marine sponges from the Berlengas natural park, western Portuguese coast
Authors: Araújo Maria Fátima , Conceição Ana , Barbosa Teresa , Teresa Lopes Maria , Humanes Madalena
Published: October 2003

Analytical studies of sponges have recently become a matter of interest, since these organisms have been reported to accumulate high levels of some elements, including heavy metals, which may have an anthropogenic origin, allowing their application as environmental pollution indicators. In the present work, 35 sponges collected in August 1998 at the Berlengas Natural Park were classified and analysed by secondary target energy‐dispersive x‐ray fluorescence spectrometry (EDXRF). Some major, minor and trace elements could be determined: Al, Si, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, As, Br, Rb, Sr, Zr, I and Pb. To assess some local influences on the sponge composition, two sediment samples were also taken from the area and analysed. Besides these elements, sponges are constituted by fairly high percentages of elements that do not emit characteristic x‐ray lines. Therefore, absorption corrections for quantitative calculations were carried out taking into account the ratio between the inelastic and elastic scattered incident radiation from a silver secondary target to calculate the mean atomic number of the light matrix. Calibration was performed using chemical compounds and standard reference materials. Precision, accuracy and detection limits for the range of elements determined by the method are particularly suitable for the chemical analysis of these organisms. Results for the sediment chemical composition indicated the existence of high Ca and low Si levels and confirmed the absence of any trace metal contamination in the region. The sponge composition showed low Si contents, even in siliceous specimens. Certain high elemental contents determined in some species indicated a clear selective bioaccumulation of particular trace elements, such as Ni, Zn and As, which is not dependent on local influences. Copyright © 2003 John Wiley & Sons, Ltd.
Investigation of interactions of nano‐particles within cells using micro‐beam imaging techniques
Authors: Ishihara Ryoko , Ide‐Ektessabi Ari , Kitamura Norio , Fujita Yoshikazu , Mizuno Yutaka , Ohta Tatsuro
Published: October 2003

A new approach was employed to investigate the interactions between cells and metal ions at the single cell level. Mouse macrophages were cultured and exposed to solutions with different concentrations of metals and exposure times. A focused beam from a synchrotron radiation source and an electron probe microanalyzer were used for elemental imaging of the cells. It was found that the intensity and distribution of the matrix elements in a single cell are closely related to the uptake of metals. Furthermore, the variation of the density the matrix elements and their localization in the cell are influenced by the uptake of metals. Copyright © 2003 John Wiley & Sons, Ltd.
Determination of trace elements in Mycobacterium fortuitum by x‐ray fluorescence spectrometry
Authors: Gresits I. , Könczöl K.
Published: October 2003

Using energy‐dispersive x‐ray fluorescence analysis with an 125I ring source, it was possible to determine the concentration of several elements, such as Mn, Fe, Cu, Zn, Br, Rb and Sr, at the µg g−1 level in a microorganism (Mycobacterium fortuitum) and in nutrient medium. It was observed that the bacteria always incorporated a fixed amount of a given element even if the concentration in the nutrient medium was different. It was possible to contaminate the cells also with Zr. The sample preparation and irradiation process developed is a non‐destructive microorganism analytical method, as about 70% of the bacteria survived the measuring process. Copyright © 2003 John Wiley & Sons, Ltd.
On the response function of solid‐state detectors, based on energetic electron transport processes
Authors: Papp Tibor
Published: October 2003

In studies of the response function of state‐of‐the‐art Si(Li) and HPGe detectors to low‐energy (2–20 keV) mono‐energetic x‐rays, various characteristic features have been observed. To trace their origin we have studied the effect of the signal processing electronics on the evolution of the electronic signal, and measured the spectral shape of energetic electrons originating from the surfaces of Si and Ge crystals and front contact materials, using a high‐energy range electrostatic electron spectrometer. From the measured electron spectra leaving the surfaces of the detector and front contact materials, and from the details of electron transport processes, the origin of the distinct features is identified and an approximate analytical form for the representation of the detector response function has been derived. It gives an excellent description of the response function and may replace the frequently applied Hypermet function. On the basis of this study, an explanation is given of the origin of the exponential tail and other various discrete structures on the low‐energy side of the primary peak. The difference in low‐energy side tailing between Si and HPGe detectors is explored. A detailed analysis of the so‐called dead layer concept is given. Characteristic structures, ‘kinks’, are predicted in the spectra measured by solid‐state detectors. Copyright © 2003 John Wiley & Sons, Ltd.
Syntheses, Structures and Magnetic Properties of Three New Extended Iron‐containing Heteropolytungstates
Authors: Yang Wen‐Bin , Lu Can‐Zhong , Lin Xiang , Zhuang Hong‐Hui
Published: October 2003

Three new extended iron‐containing heteropolytungstates were synthesized and structurally characterized: K6[{FeII(H2O)4}2(H2W12O42)]·15H2O (1), Na5[{Fe(H2O)3}2{Fe(H2O)4}0.5(H2W12O42)]·30H2O (2) and (H3O)+2[{Fe(H2O)4Fe(H2O)3}2(H2W12O42)]·20H2O (3). 1 and 3 crystallize in the monoclinic system, space group P21/n with a = 14.9967(5), b = 10.3872(3), c = 18.8237(6)Å, β = 93.407(1)°, V = 2927.1(2)Å3 and Dc = 4.151 g cm—3 for 1, and space group P21/c with a = 12.1794(4), b = 22.4938(4), c = 11.6941(3) Å, β = 105.731(2)°, V = 3083.7(1) Å3, and Dc = 4.043 g cm—3 for 3. 2 is triclinic, space group P1¯, with a = 12.121(2), b = 12.426(3), c = 13.247(3)Å, α = 68.33(3), β = 71.33(3), γ = 71.44(3)°, V = 1710.7(6)Å3 and Dc = 3.735 g cm—3. In all cases, the structures are based on paradodecatungstate polyoxoanions, which are linked by iron ions into chains, layers and a three‐dimensional structure for 1, 2 and 3, respectively.
Copper(II) Complexes with N, N'‐Bis(picolinidene‐N‐oxide)‐2‐hydroxy‐1, 3‐diaminopropane: Designing Binuclear Entities and Helical Chains by Versatile Ligand
Authors: Cheng Peng , Zhang Lei Z. , Bu Wei‐Ming , Peng Jiu‐He , Yan Shi‐Ping , Liao Dai‐Zheng , Jiang Zong‐Hui
Published: October 2003

Three novel copper(II) complex [Cu2(bpa)(μ‐PhCO2)](ClO4)2 (1), [Cu2(bpa) (μ‐pyz)](ClO4)2 (2), and [Cu(Hbpa)](ClO4)2·2CH3CN (3) have been synthesized by the reaction of Hbpa with Cu(ClO4)2·6H2O in the presence and absence of exogenous ligands (where Hbpa = N, N'‐bis(picolinidene‐N‐oxide)‐2‐hydroxy‐1, 3‐diamino‐propane). Molecular structures of these compounds have been elucidated by single crystal X‐ray diffraction. 1 and 2 are both binuclear complexes in which two copper atoms are linked by the endogenous alkoxide oxygen and the exogenous benzoate and pyrazolate ligands, respectively. 3 consists of a one‐dimensional polymeric structure, in which Hbpa functions as a bridging mode.
Synthese von Oxovanadium(V)‐halogeno‐Komplexen der tripodalen Sauerstoffliganden LR— = [η5‐(C5H5)Co{PR2(O)}3]—, R = OMe, OEt
Authors: Kläui Wolfgang , Schäfer Stefan , Wunderlich Hartmut
Published: October 2003

Durch Umsetzung der Natriumsalze der tripodalen Sauerstoffliganden LR— = [η5‐(C5H5)Co{PR2(O)}3]— (R = OMe, OEt) mit den Oxovanadiumtrihalogeniden V(O)F3 und V(O)Cl3 lassen sich stabile Verbindungen der allgemeinen Zusammensetzung [V(O)X2LR] synthetisieren. Versuche, den analogen Bromokomplex [V(O)Br2LOMe] durch Halogenidaustausch an den Komplexen [V(O)Cl2LOMe] und [V(O)F2LOMe] darzustellen, führten zu der Verbindung [VO(LOMe)2][V(O)Br4].

Die Kristallstruktur der Verbindung [V(O)Cl2LOMe] wurde bestimmt. Der Komplex kristallisiert monoklin in der Raumgruppe P21/n mit a = 9.6332(8), b = 15.0312(11) und c = 15.3742(12)Å, β = 100.181(8)°. Die Koordination des Vanadiumatoms ist oktaedrisch.
Synthesis and Crystal Structure of Hexakis(N—allylthiourea)tetracopper(I) Tetratrifluoromethanesulfonate, [Cu4{CH2=CHCH2NHC(S)NH2}6](SO3CF3)4
Authors: Olijnyk V. V. , Filinchuk Ya. E. , Pandiak N. L.
Published: October 2003

Hexakis(N—allylthiourea)tetracopper(I) Tetratrifluoromethanesulfonate, [Cu4{CH2=CHCH2NHC(S)NH2}6](CF3SO3)4 (sp.gr.P21/n, a = 13.5463(8), b = 24.129(2), c = 19.128(1)Å, β = 108.053(6)°, Z = 4, R = 0.0440 for 13548 unique reflections) was obtained by reduction of Cu(CF3SO3)2 with excess of N—allylthiocarbamide in benzene medium. Four crystallographical independent Cu atoms possess trigonal environment of three S atoms of CH2=CHCH2NHC(S)NH2 moiety and form Cu4S64+ adamantane—like fragments. The latteres are connected with CF3SO3— anions via (C)—H···F hydrogen bonds.
Syntheses and Crystal Structures of Three Polymeric Silver(I) Terephthalate Complexes with Organic N‐Donor Ligands: [Ag(pren)]2(tp)·2H2O, [Ag(en)][Ag(μ2‐tp)]·H2O, and [Ag2(μ4‐tp)(apy)2]
Authors: Zhu Hai‐Liang , Liu Xiu‐Ying , Wang Xian‐Jiang , Yang Feng , Usman Anwar , Fun Hoong‐Kun
Published: October 2003

Three polymeric silver(I) complexes with terephthalate anions as counterions or ligands, [Ag(pren)]2(tp)·2H2O (1), [Ag(en)][Ag(μ2‐tp)]·H2O (2), and [Ag2(μ4‐tp)(apy)2] (3) (where pren = 1, 2‐propylenediamine, tp =terephthalate dianion, en = ethylenediamine, and apy = 2‐aminopyridine) were synthesized and characterized by X‐ray single crystal analysis and infrared spectroscopy. 1 crystallizes in the monoclinic space group P211/c with a = 11.3221(5), b = 7.1522(3), c = 14.8128(5)Å, V = 1015.77(7)Å3, β = 122.132(2), and Z = 2. 2 crystallizes in the orthorhombic space group Pnma with a = 9.6144(6), b = 11.3465(7), c = 11.4810(7)Å, V = 1252.5(1)Å3, and Z = 4. 3 crystallizes in the monoclinic space group P21/n with a = 8.2003(5), b = 5.8869(4), c = 18.3769(11)Å, β = 92.593(1), V = 886.2(1)Å3, and Z = 4. Terephthalate dianions are not coordinated to the metal atoms in 1, but act as a μ2‐bridging ligand in 2 and as a μ4‐bridging ligand in 3.
The First Sodium Uranyl Chromate, Na4[(UO2)(CrO4)3]: Synthesis and Crystal Structure Determination
Authors: Krivovichev Sergey V. , Burns Peter C.
Published: October 2003

The first sodium uranyl chromate, Na4[(UO2)(CrO4)3], has been obtained by high‐temperature solid‐state reaction. The structure (triclinic, P1¯, Z = 2, a = 7.1548(3), b = 8.4420(3), c = 11.5102(5)Å, α = 80.203(1)°, β = 79.310(1)°, γ = 70.415(1)° V = 639.24(4)Å3 ) has been solved by direct methods and refined on the basis of F2 for all unique reflections to R1 = 0.024 [calculated on the basis of 4374 unique observed reflections (‖Fo‖ 4σF)]. The structure is based on chains of composition [(UO2)(CrO4)3] that are parallel to [1¯01]. The chains contain UrO5 pentagonal bipyramids (Ur = Uranyl) that share all equatorial corners with CrO4 tetrahedra. Cr(1)O4 and Cr(3)O4 tetrahedra bridge between two adjacent UrO5 bipyramids, whereas Cr(2)O4 tetrahedra share one corner with one UrO5 bipyramid each. The [(UO2)(CrO4)3] chains are planar and oriented parallel to (313). The Na+ cations provide linkage of the chains in the structure.
Electrochemical Synthesis of Tricyanomethyl Copper Complexes
Authors: Kamte M. Fotsing , Baumeister U. , Schäfer W.
Published: October 2003

The synthesis of tricyanomethyl copper complexes has been achieved by anodic dissolution of a sacrificial copper metal and cathodic reduction of 1, 1, 3, 3‐tetracyanopropane in acetonitrile, in the presence of triphenylphosphane used as coligand. The electrogenerated tetracyanopropyl radical anion is not stable and undergoes a cleavage leading to the tricyanomethyl anion and acrylonitrile which is electropolymerized at the cathode. The reaction solution gives a neutral dimeric binuclear copper(I) complex, bis{(μ‐ tricyanomethanido)bis(triphenylphosphane)copper(I)} [Cu(μ‐C(CN)3)(PPh3)2]2 (1). A second product of the synthesis reacts with 1, 10‐phenanthroline to give bis{cis‐(μ‐cyano)bis(triphenylphos‐phane)bis(phenanthroline)dicopper(I)}‐tricyanomethanide‐tetrafluoroborate‐diacetonitrile [cis‐{Cu2(μ‐CN)(Phen)2(PPh3)2}]2[C(CN)3] · BF4 · 2CH3CN (2). The crystal structures of 1 and 2 were determined by X‐ray analysis.
Hydrothermal Synthesis of Two New Transition Metal Coordination Polymers with Mixed Ligands
Authors: Yan Ying , Wu Chuan‐De , Lu Can‐Zhong
Published: October 2003

Hydrothermal reactions of 1, 2, 4‐benzenetricarboxylic acid, 1, 10‐phenanthroline and transition metal cations including ZnII or CoII, in basified aqueous solution gave rise to two complexes, [Zn3(btrc)2(1, 10‐phen)2(H2O)2]n (1), and [Co3(btrc)2(1, 10‐phen)2(H2O)2]n (2) (btrc = 1, 2, 4‐benzenetricarboxylate, and 1, 10‐phen = 1, 10‐phenanthroline). 1 2 crystalize isotypically in the triclinic space group P1¯. The btrc ligand acts as multi‐dentate bridging ligand in both compound 1 and 2 to link up transition metal atoms into lamella networks, which are further attached into three‐dimensional frameworks through complex hydrogen bonding and π‐π interactions. The photoluminescence spectrum for compound 1 has also been studied. The corresponding reaction with Cu2+ follows another pathway.
The [Tetra(pyridinioacetato)copper]2+ as a Tridentate Chelate to Alkaline‐Eearth Metal Cation: Crystal Structure of [Cu2Ca2(C5H5NCH2CO2)10(H2O)3](ClO4)8·H2O
Authors: Yang Yang‐Yi , Huang Zhong‐Qi , Chen Xiao‐Ming , Weng Ng Seik
Published: October 2003

A tetranuclear copper‐calcium complex of pyridinioacetate (C5H5N+CH2CO2—), namely [Cu2Ca2(C5H5NCH2CO2)(H2O)3](ClO4)8·H2O was synthesized and characterized by X‐ray crystallography. The complex crystallizes in triclinic, P1¯ (No. 2), a = 15.658(2), b = 18.260(2), c = 18.456(2)Å, α = 91.552(2), β = 94.004(3), γ = 104.928(2)°, V = 5081(1)Å3, Z = 2. In the crystal structure, a square‐planar [Cu(C5H5NCH2CO2)4]2+ entity uses three of its four carboxylate groups to chelate to a calcium atom forming a [CuCa(C5H5NCH2CO2)4]4+ dinuclear subunit, and a pair of such dinuclear subunits are linked by the two remaining pyridinioacetate ligands through the calcium atoms to furnish a tetranuclear [Cu2Ca2 (C5H5NCH2CO2)10(H2O)3]8+ cation.
Solvothermal Synthesis and Crystal Structures of Two Thioantimonate(V) Compounds with the [SbS4]3— Anion Acting as a Monodentate Ligand: [Mn(C6H18N4)(C6H19N4)]SbS4 and [Mn(C6H14N2)3]2[Mn(C6H14N2)2(SbS4)2]·6H2O
Authors: Schaefer Michael , Engelke Lars , Bensch Wolfgang
Published: October 2003

The two novel thioantimonate(V) compounds [Mn(C6H18N4)(C6H19N4)]SbS4 (I) and [Mn(C6H14N2)3][Mn(C6H14N2)2(SbS4)2]·6H2O (II) were synthesized under solvothermal conditions by reacting elemental Mn, Sb and S in the stoichiometric ratio in 5 ml tris(2‐aminoethyl)amine (tren) at 140 °C or chxn (trans‐1, 2‐diaminocyclohexane, aqueous solution 50 %) at 130 °C. Compound I crystallises in the triclinic space group P1¯, a = 9.578(2), b = 11.541(2), c = 12.297(2)Å, α = 62.55(1), β = 85.75(1), γ = 89.44(1)°, V = 1202.6(4)Å3, Z = 2, and II in the monoclinic space group C2/c, a = 32.611(2), b = 13.680(1), c = 19.997(1)Å, β = 117.237(5)°, V = 7931.7(8)Å3, Z = 4. In I the Mn2+ cation is surrounded by one tetradentate tren molecule, one protonated tren acting as a monodentate ligand and a monodentate [SbS4]3— anion yielding a distorted octahedral environment. In II one unique Mn2+ ion is in an octahedral environment of three bidentate chxn molecules and the second independent Mn2+ ion is coordinated by two chxn ligands and two monodentate [SbS4]3— units leading to a distorted octahedral surrounding. The compounds were investigated and characterized with thermal and spectroscopic methods.
Syntheses and Characterization of Zinc, Cadmium, and Mercury(II) Complexes with N‐(2‐pyridyl)carbonylaniline (L), X‐ray Crystal Structure of [Hg(L)(SCN)2]
Authors: Morsali Ali , Ramazani Ali , Mahjoub Ali Reza , Soudi Ali Akbar
Published: October 2003

The reaction of N‐(2‐pyridyl)carbonylaniline (L) with Zn(NO3)2, CdCl2, and Hg(SCN)2 gives the following complexes: [Zn(L)2](NO3)2, [Cd(L)2Cl2], and [Hg(L)(SCN)2]. The new complexes were characterized by elemental analyses and IR‐, 1H‐, 13C‐NMR spectroscopy. The crystal structure of the [Hg(L)(SCN)2] was determined by single crystal X‐ray analysis. The monomeric complex is built up of a Hg(SCN)2 unit with one N‐(2‐pyridyl)carbonylaniline (L) ligand coordinated to the Hg atom via the ring pyridinic nitrogen atom and the carbonyl oxygen atom forming a five‐membered chelate ring. The Hg atom has a distorted tetrahedral environment. There is π‐π stacking interaction between the parallel aromatic rings belonging to adjacent chain as planar species in which the mean molecular planes are close to parallel and separated by a distance of ∼ 3.5Å, close to that of the planes in graphite. The coordinated N‐(2‐pyridyl)carbonylaniline (L) molecule is involved in hydrogen bonding acting as hydrogen‐bond donors with S and N atoms from SCN— ligand as potential hydrogen‐bond acceptors. There is a shortest intermolecular contacts between the S and N atoms. The hydrogen bonding and shortest intermolecular contacts between the S and N atoms yields infinite chains parallel to the crystallographic vector c. Each molecule is bonded to two neighbors.
The First Calcium(II) Complex with the Saccharinate Ligand: Synthesis, Crystal Structure, Spectral and Thermal Characterization of Trans—diaquabis[(2—hydroxyethyl)pyridinium]bis(saccharinato)calcium(II) Disaccharinate, [Ca(sac)2(H2O)2(Hpyet)2](sac)2
Authors: Yilmaz Veysel T. , Kazak Canan , Hamamci Sevim
Published: October 2003

A new calcium(II) complex of the saccharinate ligand (sac) with 2—hydroxyethylpyridinium (Hpyet) was synthesized and characterized by elemental analysis, FT—IR spectroscopy, thermal analysis and single crystal X—ray diffractometry. The [Ca(sac)2(H2O)2(Hpyet)2](sac)2 complex crystallizes in the triclinic space group (P1¯) with the cell dimensions a = 7.4360(7)Å, b = 12.5263(12)Å, c = 12.8329(13)Å, α = 82.534(8)°, β = 75.202(8)° and γ = 89.662(8)° (293 K). The title complex consists of a complex cation and two sac anions. In the complex cation, the calcium(II) ion is six—coordinate, bonding to two aqua ligands, two Hpyet ligands andtwo sac ligands located in the trans positions. Two of the sac ions are coordinated to the calcium(II) ion through the carbonyl O atom, while the other two remain outside the coordination sphere as the counter—ions. Thermal decomposition of the complex in air results in elimination of aqua, Hpyet, and sac ions, respectively.
Synthesen und Kristallstrukturen von neuen Alkalimetall‐Selten‐Erd‐Telluriden der Zusammensetzungen KLnTe2 (Ln = La, Pr, Nd, Gd), RbLnTe2 (Ln = Ce, Nd) und CsLnTe2 (Ln = Nd)
Authors: Stöwe Klaus , Napoli Christian , Appel Stephan
Published: October 2003

Von den Verbindungen der Zusammensetzung ALnQ2 (A = Na, K, Rb, Cs; Ln = Selten‐Erd‐Metall; Q = S, Se, Te) konnten die Kristallstrukturen der neuen Telluride KLaTe2, KPrTe2, KNdTe2, KGdTe2, RbCeTe2, RbNdTe2 und CsNdTe2 durch Einkristallröntgenstrukturanalysen bestimmt werden. Sie kristallisieren allesamt im α‐NaFeO2‐Typ mit der Raumgruppe R3¯m und drei Formeleinheiten in der Elementarzelle. Die Gitterparameter lauten: KLaTe2: a = 466, 63(3) pm, c = 2441, 1(3) pm; KPrTe2: a = 459, 73(2) pm, c = 2439, 8(1) pm; KNdTe2: a = 457, 83(3) pm, c = 2443, 9(2) pm; KGdTe2: a = 449, 71(2) pm, c = 2443, 3(1) pm; RbCeTe2: a = 465, 18(2) pm, c = 2533, 6(2) pm; RbNdTe2: a = 459, 80(3) pm, c = 2536, 5(2) pm und CsNdTe2: a = 461, 42(3) pm, c = 2553, 9(3) pm. Kennzeichnend für den Aufbau des α‐NaFeO2‐Strukturtyps als geordnete Substitutionsvariante des NaCl‐Typs sind Schichten aus kantenverknüpften [(A+/Ln3+)(Te2—)6]‐Oktaedern, in denen die Besetzung durch die Kationen A+ und Ln3+ schichtweise alterniert.
A Novel 4, 4'‐Azopyridine‐Bridged Manganese Polymer: Quasi Two‐dimensional Structure and Magnetic Properties
Authors: Tang Jin‐Kui , Zhu Li‐Na , Li Xiao‐Zeng , Dong Wen , Liao Dai‐Zheng , Jiang Zong‐Hui , Yan Shi‐Ping , Cheng Peng
Published: October 2003

A novel coordination polymer {[Mn(azpy)(NCS)2(MeOH)2] · azpy}n(1) (azpy = 4, 4'‐azopyridine), has been synthesized and characterized by X‐ray diffraction. It consists of a quasi two‐dimensional network structure constructed from 1‐D chains of [Mn(azpy)(NCS)2(MeOH)2]n connected by hydrogen bonds, which creates about 13.6 Å × 17.1 Å of channels. The coordination sphere of the manganese(II) ion is a distorted octahedron. The determination of the variable temperature magnetic susceptibilities (5—300 K) shows the existence of a very weak antiferromagnetic interaction with a J value of —0.03 cm—1.
Natriumtrithiophosphat(V): Kristallstruktur und Natriumionenleitfähigkeit
Authors: Pompetzki M. , Jansen M.
Published: October 2003

Na3POS3 wurde wasserfrei durch Gefriertrocknung des entsprechenden Hydrates hergestellt. Die Kristallstruktur von Na3POS3 wurde aus Röntgen‐ und Neutronenpulverdaten bestimmt und durch simultane Rietveld‐Verfeinerung der Neutronen‐ und Röntgendaten (Cmc21, a = 9, 5105(1), b = 11, 5463(1), c = 5, 9323(1)Å, Rp = 5, 37 %, Rwp = 4, 47 %) verfeinert. Die Schwerpunkte der POS3‐Tetraeder sind im Sinne einer hexagonal dichten Packung angeordnet. Die P—O‐Bindungen sind dabei „polar”︁ parallel zur c‐Achse ausgerichtet. In der Projektion entlang [001] übereinander liegende Tetraeder stehen ekliptisch. Die Struktur von Na3POS3 steht in enger Beziehung (maximale Untergruppe) zu derjenigen von Ca3CrN3. Ab 250 °C kann Na3POS3 aufgrund seiner durchweg hohen Leitfähigkeit den schnellen Ionenleitern zugeordnet werden.
Reaktionen von Cyclostibanen (RSb)n [R = (Me3Si)2CH, n = 3; Me3CCH2, n = 4, 5] mit den Übergangsmetallcarbonyl‐Komplexen [W(CO)5(thf)], [CpxMn(CO)2(thf)], [CpxCr(CO)3]2 und [Co2(CO)8]; Cpx = MeC5H4
Authors: Balázs G. , Breunig H. J. , Lork E.
Published: October 2003

(RSb)3 [R = (Me3Si)2CH] reagiert mit [W(CO)5(thf)], [CpxMn(CO)2(thf)] oder [Co2(CO)8] zu [(RSb)3W(CO)5] (1), [RSb{Mn(CO)2Cpx}2] (2) oder [RSbCo(CO)3]2 (3). Die Reaktion von (R′Sb)n (n = 4, 5; R′ = Me3CCH2) mit [CpxCr(CO)3]2 führt zu [(R′Sb)4{Cr(CO)2Cpx}2] (4); Cpx = MeC5H4, thf = Tetrahydrofuran.
Thermogravimetric, Cyclovoltammetric, and Mössbauer Spectroscopic Investigations on Heterobimetallic Organo Derivatives of Silicon and Germanium with the 2‐(Dimethylaminomethyl)ferrocenyl Ligand (η5‐C5H5)Fe[η5‐C5H3(CH2NMe2)], FcN
Authors: Jacob Klaus , Zanello Piero , Fontani Marco , Pietzsch Claus , Bohmhammel Klaus , Lorenz Volker
Published: October 2003

The thermic decomposition of the cyclotetrametaloxanetetrols [(FcN)4M4O4(OH)4] (M= Si(1), Ge(2)) as well as the cyclohexagermoxanediol [(FcN)6Ge6O8(OH)2] (3) takes place in three defined steps. At the monomer silandiol [(FcN)2Si(OH)2] (4) only two such steps are observed. The cyclovoltammetric oxidation of the metaloxanes 1‐2 occurs in two two‐electron steps and following two one‐electron transitions. The oxidation of 3 occurs in a four‐electron process and a following two‐electron transition. Silandiol 4 is oxidized via two one‐electron transitions. The oxidation of the educt [FcNGeCl3] (5) occurs in a one‐electron step. Temperature depending 57Fe‐Mössbauer‐measurements confirm as well intervalent electron transitions in 1‐5 as the chelate stucture in 5.
Polysulfonylamine. CLXV [1] Kristallstrukturen von Metall‐di(methansulfonyl)amiden. 14 [1] Cs3Ag[(MeSO2)2N]4 und CsAg[(MeSO2)2N]2: Ein dreidimensionales und ein schichtförmiges Koordinationspolymer mit Bis(dimesylamido‐N)argentat‐Baugruppen
Authors: Latorre Violeta , Jones Peter G. , Moers Oliver , Blaschette Armand
Published: October 2003

Es werden zufällige Bildungswege und Tieftemperatur‐Röntgenstrukturen für die Koordinationsverbindungen Cs3A2[AgA2] (1) und Cs[AgA2] (2) mitgeteilt, wobei A— den fünfzähnigen Dimesylamid‐Liganden (MeSO2)2N— bezeichnet. Beide Phasen (monoklin, Raumgruppe C2/c, Z′ = 1/2) enthalten inversionssymmetrische Bis(dimesylamido‐N)argentat‐Einheiten mit exakt linearen N—Ag—N‐Gerüsten und kurzen, überwiegend kovalenten Ag—N‐Bindungen [1: 213, 5(2), 2: 213, 35(12) pm]; in beiden Fällen ist die Koordinationszahl des Silberions durch vier innere und zwei äußere Ag···O‐Sekundärbindungen auf 2 + 6 erhöht. Das dreidimensionale Koordinationspolymer 1 besteht aus alternierenden Schicht‐Substrukturen der Konstitution [{Cs(1)}{A}4/2]— mit Cs(1) auf zweizähligen Drehachsen bzw. [{Cs(2)}2{AgA2}4/4]+ mit Cs(2) auf allgemeinen Lagen. Innerhalb der Substrukturen erreichen die zwei Arten von Caesiumionen annähernd planare (O4)‐Umgebungen, während die endgültigen Koordinationssphären durch Zwischenschicht‐Bindungen zu O6 für Cs(1) und O8N für Cs(2) erweitert werden. Im Gegensatz dazu handelt es sich bei 2 um eine echte Schichtstruktur. Die Schichten enthalten, in alternierender Anordnung, Ketten von Cs+‐Ionen entlang zweizähliger Drehachsen und [AgA2]—‐Stapel mit innerer Stabilisierung durch Ag···O‐Sekundärbindungen sowie schwache Wasserstoffbrücken der Art C—H···O; für Cs+ resultiert eine (O8)‐Umgebung. Beide Strukturen weisen ein dreidimensionales (C—H···O)‐Netzwerk auf.
Eine neue Modifikation der Laves‐Phase CaLi2
Authors: Fischer Dieter , Jansen Martin
Published: October 2003

Durch simultane Bedampfung eines Saphirsubstrates mit Calcium und Lithium wurde eine neue Modifikation von CaLi2 (β‐CaLi2) erhalten. Diese kristallisiert kubisch im MgCu2‐Typ (Fd3¯m, a = 885.6(1) pm, Rp=5.1 %, Rwp=6.6 %, Strukturanalyse mittels Rietveld‐Methode) und wandelt sich bei 150 °C in das bekannte hexagonale α‐CaLi2 um. Das thermische Verhalten wurde durch temperaturaufgelöste Röntgenpulveruntersuchungen studiert.
Vergleichende Untersuchungen zur Struktur von 4‐Dimethylaminopyridin‐Addukten
Authors: Thomas Florian , Bauer Tillmann , Schulz Stephan , Nieger Martin
Published: October 2003

Lewis‐Säure/Base‐Addukte des Typs dmap—MMe3 (M = Al 1, Ga 2, In 3, Tl 4) sowie dmap—AlCl3 (6) und dmap—Al(t‐Bu)3 (7) wurden durch Reaktion von MR3 mit 4‐Dimethylaminopyridin (dmap) synthetisiert, während dmap—AlH3 (5) ausgehend von AlH3·Et2O erhalten werden konnte. 1—7 wurden durch NMR‐ (1H, 13C{1H}) und Massenspektrometrie sowie mittels Elementaranalyse eindeutig charakterisiert. Zusätzlich wurde von allen Verbindungen eine Einkristallröntgenstrukturanalyse durchgeführt. Ein Strukturvergleich zeigt die Einflüsse elektronischer (Lewis‐Acidität des Gruppe 13‐Zentralatoms) und sterischer Wechselwirkungen auf Struktur und Stabilität derartiger Lewis‐Säure/Base‐Addukte.
LaCl(BO2)2 und Er2Cl2[B2O5]: Zwei Chlorid‐Oxoborate dreiwertiger Lanthanide
Authors: Nikelski Tanja , Schleid Thomas
Published: October 2003

Er2Cl2[B2O5] entsteht einkristallin bei der Umsetzung von ErCl3 mit den Sesquioxiden Er2O3 und B2O3 mit einem Überschuß von ErCl3 als Flußmittel in evakuierten Quarzglasampullen nach zwei Wochen bei 850 °C. Die Verbindung fällt in langen, rosafarbenen Nadeln an und ist luft‐ und hydrolysestabil. Einkristalle von LaCl(BO2)2 bilden sich bei der Umsetzung von La2O3, LaCl3 und B2O3 in einem Überschuß von B2O3 als Flußmittel in evakuierten Quarzglasampullen nach vier Wochen bei 900 °C. LaCl(BO2)2 kristallisiert in dünnen, farblosen, luft‐ und wasserbeständigen Nadeln, die aufgrund ihres faserigen Habitus stark zu Wachstumsverzwillingung neigen. Die Kristallstruktur von Er2Cl2[B2O5] (orthorhombisch, Pbam; a = 1489, 65(9); b = 1004, 80(6); c = 524, 86(3) pm; Z = 4) enthält zwei kristallographisch unterschiedliche Erbium‐Kationen. (Er1)3+ wird von sieben Anionen pentagonal‐bipyramidal umgeben, während (Er2)3+ von nur sechs Anionen oktaedrisch koordiniert vorliegt. Die planaren Oxodiborat‐Einheiten [B2O5]4—, die aus zwei eckenverknüpften [BO3]3—‐Dreiecken bestehen, liegen gemäß {([BOO]2)4—} isoliert vor. LaCl(BO2)2 kristallisiert isotyp mit PrCl(BO2)2 triklin in der Raumgruppe P1¯ (a = 423, 52(4); b = 662, 16(7); c = 819, 33(8) pm; α = 82, 081(8); β = 89, 238(9); γ = 72, 109(7)°; Z = 2). Die charakteristische Baueinheit besteht aus unendlichen Ketten eckenverknüpfter [BO3]3—‐Dreiecke. Diese quasi‐planaren, zickzack‐förmigen Ketten der Zusammensetzung {[(B1)OO(B2)OO]2—} (≡ {[BO2]—} verlaufen entlang [100]. Die La3+‐Kationen weisen eine Koordinationszahl von zehn auf und werden von drei Cl—‐ und sieben O2—‐Anionen koordiniert.
Multi‐dimensional Copper(II) Coordination Polymers via Self‐assembly Induced by Sodium Ions
Authors: Chen Xiao‐Yan , Shi Wei , Cheng Peng , Chen Jiu‐Tong , Yan Shi‐Pin , Liao Dai‐Zheng , Jiang Zong‐Hui
Published: October 2003

Two novel copper(II) coordination polymers, [CuNa2(Hnta)2]n (1) and {[CuNa2(pht)2(H2O)]·H2O}n (2) (H3nta = nitrilotriacetate acid, H2pht = o‐phthalic acid), have been synthesized and characterized.The sodium ions play an important role in the formation of the multi‐dimensional structures. The X‐ray structure of [CuNa2(Hnta)2]n (1) is three‐dimensionally cross‐linked with building blocks [Cu(Hnta)2]2—connected by three sodium ions. The structure of {[CuNa2(pht)2(H2O)]·H2O}n (2) can be described as pht units connected by Na ions via Na—O bonds to form chains, which are linked by CuII ions to make a 2D network. The IR spectra and thermal properties are also reported.
Synthesis of Ethylene‐bridged Heterocyclic Bidentate P(III)N‐Ligands — Oxidation and Complexation Studies
Authors: Lu Yingzi , Freytag Matthias , Jones Peter G. , Schmutzler Reinhard
Published: October 2003

A series of phosphor(III)inanone ligands 4‐7, linked by ethylene bridges between the nitrogen atoms of the heterocyclic rings, were synthesized by the reaction of the bis‐PCl derivative 3 with the appropriate trimethylsilylamines. The bis‐phosphor(V)inanone compounds 8‐11 were obtained by the oxidation of 4‐7 with hexafluoroacetone (HFA). Oxidation of 4 and 6 with tetrachloro‐orthobenzoquinone (TOB) gave the bis‐phosphor(V)inanones 12 and 13. The reaction of 4‐6 with [Pt(COD)Cl2] led to the platinum complexes 14‐16. All the σ3‐phosphorinanone compounds 4‐7 and the σ5‐phosphorinanone compounds 8‐10, 12 and 13 exist as a mixture of two conformers, as indicated by two signals in the 31P‐NMR spectra. However, compounds 9 and 11 exist as single conformers, both display only one sharp singlet in the 31P‐NMR spectra. The Pt‐complexes 15 and 16 contain two conformers; one conformer of 16 could be isolated by crystallization. X‐ray crystal structure determinations for compounds 8, 14 and 16 were conducted, revealing inversion symmetry for 8 and cis arrangement for 14 and 16.
Synthesis and Structural Characterization of Two New 2D Isophthalate‐bridged Copper(II) Polymers Based on Tricopper Units
Authors: Zhang Qiang , Ye Bao‐Hui , Ren Chun‐Xia , Chen Xiao‐Ming
Published: October 2003

Two new neutral polymeric layer compounds, [Cu3(bpy)2(Hip)2(ip)2] (1) and [Cu3(phen)2(Hip)2(ip)2] (2) (bpy = 2, 2′‐bipyridine, phen = 1, 10‐phenanthroline, ip = isophthalate), have been synthesized under hydrothermal conditions and characterized by X‐ray crystallography. Complex1crystallizes triclinic,P1¯ (No. 2),a= 10.352(5),b= 10.859(6),c= 11.602(6)Å, α = 83.25(1),β= 84.71(1),γ= 66.19(1)°,V= 1183.5(11)Å3,Z= 1;2triclinic,P1¯ (No. 2),a= 10.375(1),b= 10.668(1),c= 11.758(1)Å, α = 83.179(2),β= 86.228(2),γ= 71.187(2)°,V= 1222.7(2)Å3,Z= 1. The complexes consist of trinuclcear copper units that are bridged via two ip ligands forming zigzag polymeric chains. These chains are further extended into layers via aromatic π‐π interactions as well as hydrogen bonds between the free carboxyl groups and carboxylates.