Search results for "ECU"

Lewis Base Catalyzed Intramolecular Reduction of Salicylaldehydes by Pinacol-Derived Chlorohydrosilane

2018

Herbicidal value of essential oils from oregano-like flavour species

2017

ABSTRACTChemical composition and phytotoxicity of oregano, marjoram and Thymus mastichina essential oils against Portulaca oleracea L., Lolium multiflorum Lam. and Echinochloa crus-galli (L.) Beauv. has been investigated. Seventy-seven compounds reaching 97.3% and 99.4% were identified by gas chromatography–mass spectrometry. Carvacrol (60.42 ± 0.07%), p-cymene (15.52 ± 0.02%) and γ-terpinene (5.19 ± 0.02%) were the main compounds in oregano essential oil, whereas large amounts of 1,8-cineol (59.59 ± 0.85%, 49.49 ± 0.37%), linalool (13.05 ± 0.04%, 5.66 ± 0.01%) and α-terpineol (3.36 ± 0.10%, 5.59 ± 0.01%), followed by β-pinene (4.35 ± 0.39, 5.54 ± 0.01%) and α-pinene (4.11 ± 0.53, 4.28 ± 0.…

The separation of cis- and trans-1,3-cyclohexanediol isomers by copper complexation. Crystal structures of cis-1,3-cyclohexanediol and copper(II) chl…

2002

Abstract A 1:1 complex between copper(II) chloride and cis-1,3-cyclohexanediol has been synthesized and its crystal structure determined. The structure is composed of two different dinuclear [CuCl2(c-13chd)]2 units in which the copper(II) ions are surrounded by the two oxygen atoms of the diol and the two halide ions in a distorted cis-square planar arrangement in both cases. A fifth coordination site is occupied by a halide ion in one dinuclear unit for both copper ions and an O atom belonging to the adjacent CuCl2(c-13chd) moiety in the other dinuclear unit for both copper ions, thus forming a distorted square pyramidal geometry for the metals in all cases. The ability of CuCl2 to prefere…

Enhancement of the Intermolecular Magnetic Exchange through Halogen···Halogen interactions in Bisadeninium Rhenium(IV) Salts

2017

Two novel ReIV salts of general formula [H2ade]2[ReIVX6]X2·4H2O [H2ade2+ = 9H-adenine-1,7-diium; X = Cl(1) and Br(2)] have been synthesized and magneto-structurally characterized. 1 and 2 are isostructural salts that crystallize in the orthorhombic system with space group Fdd2. Both compounds are made up of discrete mononuclear [ReIVX6]2- and X- anions and doubly protonated adenine cations. The six-coordinate rhenium(IV) ion is bonded to six halide ligands [X = Cl (1) and Br (2)] in an octahedral geometry. Short intermolecular ReIV−X···X−ReIV interactions, as well as ReIV−X···H−N(H2ade) and ReIV−X···H−Ow hydrogen bonds, are present in the crystal lattice of 1 and 2. Magnetic suscep-tibility…

Synthesis, Crystal Structure and Magnetic Properties of Heteropolynuclear Re IV M II Complexes Based on the Robust [ReCl 5 (pyzCOO)] 2– Unit (pyzCOO …

2016

The syntheses, crystal structures and magnetic properties of four rhenium(IV) compounds of formulae NBu4[ReCl5(pyzCOOH)]·H2O (1), [ReCl5(µ-pyzCOO)M(dmphen)2]·2CH3CN [M = Ni (2) and Co (3)] and {[ReCl5(µ3-pyzCOO)]2Mn2(dmphen)3}n (4) (NBu4 = tetra-n-butylammonium cation, pyzCOOH = 2-pyrazinecarboxylic acid, dmphen = 2,9-dimethyl-1,10-phenanthroline) are reported herein. Compound 1 was obtained by the reaction of NBu4[ReCl5(dmf)] (dmf = dimethylformamide) with pyzCOOH in acetone, whereas the other complexes were obtained by the reaction of 1 with M(ClO4)2·6H2O [M = Ni (2), Co (3), Mn (4)] and dmphen in acetonitrile. Complex 1 is a mononuclear compound, 2 and 3 are neutral heterodinuclear compl…

Linking PO43− and HAsO42− anions with a dinuclear [ZnII2] complex: Formation and stabilization of novel decanuclear metallomacrocyclic [ZnII10] and t…

2017

The linkage of PO43- and HAsO42--anions with a newly synthesized five-coordinate dinuclear zinc complex, Zn-2(cpdp)(H2O)(2)]Cl (1) H(3)cpdp =N,N'-bis2-carboxybenzomethyl]-N,N'-bis2-pyridylmethyl]-1,3diamino propan-2-ol], has been explored. In methanol-water, the reaction of 1 with Na2HPO4 center dot 2H(2)O and Na2HAsO4 center dot 7H(2)O/NaBr separately, at ambient temperature, yielded the novel phosphate-bridged decanuclear zinc cluster, (H3O)(4)Zn-10(cPdP)(4)(mu(5)-PO4)(2)(H2O)(6)](6 center dot Cl)center dot 53H(2)O (2) and hydrogen arsenate bridged tetranuclear zinc cluster, Na-2Zn-4(cpdp)(2)(mu(4)-HAsO4)]ClBr center dot 13H(2)O (3), respectively. Analysis of the single crystal X-ray stru…

Insights into the crystal packing of phosphorylporphyrins based on the topology of their intermolecular interaction energies

2014

Four metal complexes of 5,15-bis(diethoxyphosphoryl)-10,20-diphenylporphyrin 1M (M = Cd(II), Ni(II), Pd(II), and Pt(II)) were synthesized and crystallographically characterized. The crystal organization patterns were analyzed using DFT (B97-D3/def2-SVP) calculations of the intermolecular interaction energies between complexes in the crystals. For the systematic analysis of crystal packing, the calculations were extended to previously reported compounds 1M (M = H2, Cu(II), and Zn(II)). Quantitative analysis of the interaction energies shows the essential role of weak intermolecular interactions, such as C-H⋯O, C-H⋯π and M⋯π, in the formation of basic structural motifs and their organization …

Hybrid GMP–polyamine hydrogels as new biocompatible materials for drug encapsulation

2020

Here we present the preparation and characterization of new biocompatible materials for drug encapsulation. These new gels are based on positively charged [1+1] 1H-pyrazole-based azamacrocycles which minimise the electrostatic repulsions between the negatively charged GMP molecules. Rheological measurements confirm the electroneutral hydrogel structure as the most stable for all the GMP-polyamine systems. Nuclear magnetic resonance (NMR) was employed to investigate the kinetics of the hydrogel formation and cryo-scanning electron microscopy (cryo-SEM) was used to obtain information about the hydrogel morphology, which exhibited a non-homogeneous structure with a high degree of cross-linking…

Modulation of the ordering temperature in anilato-based magnets

2019

Abstract Four new 2D honeycomb anilato-based ferrimagnets with Mn(II) and Cr(III) have been prepared and characterized. These compounds, formulated as (NBu4)[MnCr(C6O4X2)3(PhCHO)]·PhY (X/Y = Cl/H (1), Br/H (2), Cl/CHO (3) and Br/CHO (4) show that it is possible to include benzaldehyde as a co-ligand coordinated to the Mn(II) metal atom in these 2D ferrimagnets. This inclusion increases the coordination number of Mn(II) to seven resulting in a change in the ordering temperatures of these 2D ferrimagnets (from ca. 10–11 K to ca. 7 K). Here we show the role played by the additional benzaldehyde ligand and by the crystallization solvent molecules (benzene in 1 and 2 and benzaldehyde in 3 and 4)…

Enhanced Interplay between Host–Guest and Spin-Crossover Properties through the Introduction of an N Heteroatom in 2D Hofmann Clathrates

2021

Controlled modulation of the spin-crossover (SCO) behavior through the sorption-desorption of invited molecules is an extensively exploited topic because of its potential applications in molecular sensing. For this purpose, understanding the mechanisms by which the spin-switching properties are altered by guest molecules is of paramount importance. Here, we show an experimental approach revealing a direct probe of how the interplay between SCO and host-guest chemistry is noticeably activated by chemically tuning the host structure. Thus, the axial ligand 4-phenylpyridine (4-PhPy) in the 2D Hofmann clathrates {Fe(4-PhPy)2[M(CN)4]} (PhPyM; M = Pt, Pd) is replaced by 2,4-bipyridine (2,4-Bipy),…