Über das Anlagerungsvermögen von Salicylaldehydimin-Komplexen des Nickels und Kupfers. I

Chelate complexes of SCHIFF bases of salicylaldehyde with bivalent nickel and copper often show an association of molecules in the crystal lattice. With SCHIFF bases of one-sided substituted, ethylene and propylene diamines the IR-spectrum shows only the coordination number four for Ni and Cu. Prom the IR absorption of the secondary amine group of diethylenetriamine, dipropylentriamine, and triethylenetetramine, a definite shifting of the NH frequency in the copper salts is observed. With the nickel salts the shifting is not so strong and sometimes indefinite. Therefore the occupation of a fifth coordination site at the two metal atoms is proved definitely in the case of the copper compounds, whereas for the nickel compounds investigated this seems to be only probable in most cases.     

Über das Anlagerungsvermögen von Salicylaldehydiminokomplexen des Nickels und Kupfers. II

A lot of nickel and copper complexes of Schiff bases were prepared and investigated for their solubility behaviour. Amine components and aldehyde components used see ?Inhaltsübersicht?. As far as investigated, the solubility of those compounds containing 4. and 5. is poor in most solvents, but it is better in pyridine. N.N′-pentamethylene-bis(salicylideneiminato)-nickel(II) is trimeric in pyridine. The copper and nickel salts containing the bulky amines 7.,8. and 9. are oligomeric (n = 2 to n = 5) in bromoform and pyridine. The salts containing 11. are monomeric in pyridine. With Stuart models it is possible to construct dimers containing 7. and 9. as amine components having square planar configuration around the metal atom. With strongly distorted tetrahedral configuration it is possible to obtain monomers. With 17., completely insoluble high polymeric compounds were obtained, whereas with 12. oligomers are found.     

Über das fluktuierende Verhalten von triphenylmethylsubstituierten Cyclopentadienyl-Metallverbindungen

The fluxional behaviour of triphenylmethyl substituted cyclopentadienyl metal compounds ¹H-NMR. spectroscopy has been used to study the influence of the triphenylmethyl substituent on the metallotropic rearrangement in C₅H₄(CPh₃)Si(CH₃)₃ and C₅H₄ (CPh₃)Sn(CH₃)₃. The most likely mechanism corresponds to a degenerate metal exchange between two neighbouring ring positions. The AA'XX' spectrum of the cyclopentadienyl ring protons in C₅H₄(CPh₃)Sn(CH₃)₃ has been analysed under rapid exchange conditions. The free energy of activation for the sigmatropic [1,5]-Sn shift has been measured by comparison with computer simulated spectra for slow exchange.     

Photokatalytische Systeme. LXVIII. Second-Sphere-Photoreaktion von Cyanometallaten mit Diphenyliodoniumionen

Photocatalytic Systems. LXVIII. Second-Sphere Photoreaction of Cyanometallates with Diphenyliodonium Ions Solutions of diphenyliodonium salts of [Ru(CN)₆]^4?, [Fe(CN)₅DMSO]^3?, [Mo(CN)₈]^4?, [Mn(CN)₅NO]^3?, [W(CN)₈]^4?, and [Fe(CN)₆]^4? in methanol and other non-aqueous solvents exhibit new, broad absorptions in the visible spectral range because of second-sphere interactions due to ion pair charge-transfer (IPCT). With the decreasing of the acceptor ability of the solvent and decreasing oxidation potential of the complex anion the absorptions are red-shifted. Substituents at the diphenyliodonium ion do not influence the absorption maxima. Irradiation into the IPCT bands leads to an efficient long-wavelength photooxidation of cyanometallate in competition with the photoinduced catalytic destruction of diphenyliodonium /ions.     

Über das kubische Vanadiummonoxid

Reinvestigation of the homogeneity range of the cubic vanadium monoxide phase showed that this oxide exhibits two closely related phase sections (VO_0.86 to VO_0.91,and VO_1.05 to VO_1.25) divided by a miscibility gap. This largely confirms observations of VOL'F et al.     

Über das Auftreten von Polysulfan-diphosphonaten bei der Umsetzung von Monothiophosphat mit Disulfan-diphosphonat

On the Formation of Polysulphane Diphosphonates by the Reaction of Monothiophosphonate with Disulphane Diphosphonate In acid solution SPO reacts with S₂P₂O forming higher polysulphane diphosphonates. The formation of S₃P₂O and S₄P₂O is proved by evaluation of the double labelling with ³⁵S? ³²P after high paper electrophoresis.     

Stoffwechselprodukte von Mikroorganismen. 190. Mitteilung. Über das 4-Oxo-homotyrosin,ein Abbauprodukt des Echinocandins B

D , L -4-Oxo-homotyrosine was synthesized by the acetylaminomalonic ester pathway. The optical resolution was carried out by means of the enzyme acylase I. The L -configuration of the enzymatically produced amino acid was confirmed by degradation to L -aspartic acid. 4-Oxo-homotyrosine obtained by degradation of the polypeptide antibiotic echinocandine B has D -configuration, but his optical purity is low. A hypothetical explanation for its formation from the (2 S, 3 S, 4 S)-3,4-dihydroxyhomotyrosine residue of echinocandine B is proposed.     

Über die Systeme Alkalimetallbromid/Calciumbromid

The Systems Alkali Metal Bromide/Calcium Bromide The phase diagrams of the systems ABr/CaBr₂ (A ? Cs, Rb, K, Na) were elucidated by means of difference thermal analysis and confirmed by X-ray powder patterns. Compounds ACaBr₃ exist in all systems with several modifications. They belong to the perovskite type of structure or to its deformation varieties, with exception of NaCaBr₃ (ilmenite-type), which is stable only at higher temperature and T-KCaBr₃ (TlPbI₃ type). Na₆CaBr₈ is the first SUZUKI phase with NaBr; Cs₂CaBr₄ is the first 2:1 ternary bromide with octahedral coordination of the M²⁺ ion. Octahedral environment exists also in Rb₄CaBr₆, Cs₃Ca₂Br₇, and Cs₄Ca₃Br₁₀.     

Über die Eigenschaften des Xp-Teils von AnBXp-Kernresonanzspektren

The subspectral breakdown of the X-part in A_nBX_p-spectra is derived and the general properties of the subspectra are discussed. The nature of the asymmetry of X_p-spectra for n > 1 is explained and conditions for its disappearance are given. The degeneration of the X_p-part into deceptively simple spectra is described and degeneration conditions are derived. The determination of relative signs of coupling constants is discussed.     

Über das Verhalten von Diorganophosphinsäurehalogeniden gegenüber LEWIS-Säuren und LEWIS-Basen

From R₂POCl [R = (CH₃)₂N; C₆H₅] and Ag[SbF₆] in polar solvents, extremely hygroscopic donor-acceptor complexes R₂POF · SbF₅ have been obtained according to equation (1) in ?Inhaltsübersicht”?. The interaction between R₂POCl (R = C₆H₅; CH₃) and the Lewis base KP(C₆H₅)₂ proceeds via a complicated redox mechanism (see equat. (2) in ?Inhaltsübersicht”?) yielding diorganophosphinic anhydride, the mixed diorgano-diphenyl-diphosphine, and tetraphenyl-diphosphine. All these reaction products have been identified by IR-spectroscopic, analytic and other chemical methods.     

Über Fluoride des zweiwertigen Eisens. Zum Aufbau von CsFeF3

Fluorides with Divalent Iron: On the Structure of CsFeF₃ By ?reaction with the wall”? according to 3 CsF + 2 FeF₃ + Fe_wall = 3 CsFeF₃ we obtained for a first time colourless single crystals of CsFeF₃. The lattice constants were redetermined with a = 616.39(6) pm, c = 1487.02(15) pm (Four circle diffractometer PW 1100, AgK$ \bar \alpha $, R = 4.33%, R_w = 2.79%). CsFeF₃ crystallizes isotypic to BaTiO₃ in the space group P6₃/m mc. Parameters see text. The Madelung Part of Lattice Energy, MAPLE, and the ?Effective Coordination Numbers”?, ECoN, via the ?Mean Fictive Ionic Radii”?, MEFIR, are calculated and discussed.     

Anil-Synthese. 19. Mitteilung. Über die Herstellung von Stilbenyl-Derivaten des Isoxazols

Preparation of Stilbenyl Derivatives of Isoxazoles Schiff's bases derived from 3- and 5-(p-formylphenyl)-phenylisoxazoles and o- or p-chloroaniline are reacted with various p-tolyl substituted aromatic heterocycles in the presence of dimethylformamide and potassium hydroxide or potassium t-but-oxide to yield the corresponding heterocyclic substituted stilbenes (‘Anil synthesis’). 5-[4-(Chlorphenylimino-methyl)phenyl]-phenylisoxazoles react less readily than the corresponding 3-isomers.     

Anil-Synthese. 21. Mitteilung. Über die Herstellung von stilbenyl-derivaten des pyrazols

Preparation of Stilbenyl Derivatives of Pyrazoles Schiffs bases derived from 1-, 3- and 5-(p-formylphenyl)phenylpyrazoles and p-chloroaniline are reacted with various p-tolyl substituted aromatic heterocycles in the presence of dimethylformamide and potassium hydroxide or potassium t-butoxide to yield the corresponding heterocyclic substituted stilbenes (anil synthesis). Introduction of a chloro substituent in the 4- and 4,5-positions of the pyrazole system causes a decrease in yield and a hypsochromic shift in the absorption and fluorescence maxima of the title compounds.