Tris(methyltrihydroborato)(tetrahydrofuran)ytterbium(III) complex: structure and volatility

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Synthesis,structures and magnetic properties of two iron(ii) tris(pyridyl)phosphine sulfide complexes

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Electrochemical behaviour of mono- and oligonucleotides: Part III. Adsorption parameters of the dilute and compact adsorption layer of adenosine and adenine mononucleotides

Extended systematic studies on the adsorption of protonated adenosine and adenine mononucleotides by the joint application of the small amplitude method out-of-phase a.c. voltammetry and the large amplitude method rapid single sweep voltammetry have established all the data for the quantitative elucidation of the interfacial behaviour of these substances of particular biological significance. Over a wide potential range one has a dilute adsorption layer while within the potential range of maximum adsorption at elevated bulk concentrations formation of a compact film is observed. The adsorption can be described quantitatively for both types of adsorption layers by single and double step Frumkin isotherms, respectively. The resulting adsorption parameters are evaluated and the conclusions on the respective interfacial behaviours, orientations and interactions of these substances are summarized and compared with their corresponding interfacial behaviour when they are integrated as building stones in oligo-and polynucleotides and DNA. Moreover, the adsorption parameters of adenosine typical for a purine-type nucleoside are compared with those of cytidine typical for pyrimidine nucleosides. In a general methodological sense the study is a good example of the particular potentialities of the joint application of the two chosen voltammetric methods for the quantitative elucidation of the involved interfacial behaviour of strongly surface active substances which are able also to undergo electrochemical reduction or oxidation at certain potentials.     

Copper(I) complex with BINAP and 3,5-dimethylpyrazole: synthesis and photoluminescent properties

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Synthesis and properties of 1,3-diphenyl-5-(benzothiazol-2-yl)-6-R-verdazyls

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Novel 2-alkoxy- and 2-alkylthio-substituted pyrimidines containing 2-(1-methyl-1H-pyrrol-2-yl)vinyl moieties: optical and electrochemical properties

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Synthesis of 1-(hydroxyaryl)furo[3,4-c]pyridines from 1-amino(alkoxy)furo[3,4-c]pyridines and (poly)phenols

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New all-cis-tetra(p-tolyl)cyclotetrasiloxanetetraol and its functionalization

New all-cis-tetra(p-tolyl)cyclotetrasiloxanetetraol and its derivatives with Si(CH = CH₂)Me and Si(H)Me₂ groups have been prepared and characterized by IR and NMR spectroscopy, GPC, mass spectrometry, TGA and DSC. Molecular and crystalline structures of the tetraol and its derivative with four Si(CH = CH₂)Me groups have been determined by single-crystal X-ray diffraction.     

Crystal structure and nontrivial magnetic properties of CuII binuclear complex based on 4-methyl-2,6-bis{[2-(4,6-dimethyl-pyrimidin-2-yl)hydrazono]methyl}phenol

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Batch and in-flow kinetic resolution of racemic 1-(N-acylamino)alkylphosphonic and 1-(N-acylamino)alkylphosphinic acids and their esters using immobilized penicillin G acylase

The kinetic resolution of racemic 1-(N-acylamino)alkylphosphonic acids 3 (R³ = OH) and their dimethyl esters 1, as well as 1-(N-acylamino)alkylphosphinic acids 4 (R³ = H or Ph) using penicillin G acylase (PGA) immobilized on three types of mesoporous silicas in both a batch slurry system and in a continuous-flow reactor was studied. The initial hydrolytic deacylation rates in the presence of those catalysts were measured and the relationships between the substrate structure and the enzyme efficiency are discussed. The stereospecific hydrolysis of the N-acyl group of both racemic N-acylated phosphorus analogues of amino acids and their esters catalyzed by the immobilized PGA proved to be a highly effective method for the kinetic resolution of all the investigated compounds, with the stereochemical preference of PGA for (R)-substrates.     

Thermal polycondensation of hexakis(p-acetylphenoxy)-cyclotriphosphazene

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Deprotonation of 1,1′-methylenebis[4-tert-butyl-2-(diphenylphosphino)-benzene] and its analogues: synthesis and crystal structure of {5-But-2-[4-But-2-(Ph2P)C6H3(Ph)CH]C6H3P(Ph)K(OEt2)}2

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Stability of nickel bis(dicarbollide) complexes

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Studies on the effects of doping cesium metal(III) halides of the type Cs3MIII2X9 (MIII = Sb or Bi, X = Cl or Br)

A series of compounds, Cs₃M^III₂X₉ (M^III = Sb and Bi, X = Cl or Br) are doped with impurity ions (Ba²⁺, Ca²⁺, Sn²⁺, Pb²⁺, Mg²⁺, Fe²⁺, Tl³⁺, In³⁺, Se⁴⁺). Lattices doped with Sn(II), Pb(II) and Se(IV) are colored. Sn-119m Mössbauer data are consistent with the donation of Sn-5s electron density from tin(II) to a conduction band to give a pseudo-tin(IV) electronic environment.     

NMR investigation of photoinduced chiral inversion in (R)/(S)-naproxen–(S)-tryptophan linked system

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Oxo transfer reaction: Dioxido and monooxidovanadium(V) complexes

A dioxidovanadium(V) complex of type [(L_ONOH^?)(VO₂)] (1) was isolated where L_ONOH₂ is a tridentate ONO donor benzhydrazide ligand. 1 undergoes an oxo transfer reaction with triphenylphosphine in presence of 8-hydroxyquinoline (HQ) and affords a monooxidovanadium(V) complex of type [(L_ONO^2?)(VO)(Q^?)] (2). 1 and 2 were substantiated by elemental analyses, ESI-mass, IR, ¹H NMR, ⁵¹V NMR and UV–vis spectra. The molecular geometries of 1 and 2 were authenticated by single crystal X?ray crystallography. UV–vis absorption spectra of 1 and 2 display bands respectively at 325 and 320 nm due to oxido → vanadium(V) charge transfer transitions. 1 exhibit an irreversible cathodic peak at ?0.44 V whereas 2 displays a reversible cathodic wave at ?0.60 V in cyclic voltammogram due to the VO³⁺/VO²⁺ redox couple.     

Phosphorylation of (1-aryl-1-hydroxymethyl)phosphonates

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A convenient synthesis of copper(II) bis[5-(pyridin-2-yl-methylidene)-2-thiohydantoin] complexes

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Regioselective functionalization of gem-bis(trifluoromethylated) alkanols

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Enantiopure vicinally trisubstituted all-cis-bis(hydroxymethyl)-cyclopentenols and their derivatives

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