Phosphanimin- und Phosphaniminato-Komplexe von Magnesium. Die Kristallstrukturen von [MgBr1,25I0,75(Me3SiNPMe3)(OEt2)], [MgI2(Me3SiNPMe3)2], [Mg2I2(Me3SiNPMe2CH2)Me3SiNPMe2CH2CH(Me)O)(OEt2)] und [MgBr(NPMe3)]4·C7H8

Phosphaneimine and Phosphoraneiminato Complexes of Magnesium. The Crystal Structures of [MgBr_1,25I_0,75(Me₃SiNPMe₃)(OEt₂)], [MgI₂(Me₃SiNPMe₃)₂], [Mg₂I₂(Me₃SiNPMe₂CH₂)(Me₃SiNPMe₂CH₂CH(Me)O)(OEt₂)], and [MgBr(NPMe₃)]₄ · C₇H₈ By reactions of the silylated phosphaneimine Me₃SiNPMe₃ with the Grignard reagents EtMgBr and MeMgI, respectively, the carbanionic phosphoraneiminato derivatives [XMg(CH₂PMe₂NSiMe₃)]_n (X ? Br, I) can be isolated as main products. The by-products of these reactions, [MgBr_1.25I_0.75(Me₃SiNPMe₃)(OEt₂)], [MgI₂(Me₃SiNPMe₃)₂] and [Mg₂I₂(CH₂PMe₂NSiMe₃)(O(Me)CHCH₂PMe₂NSiMe₃)(OEt₂)] were identified by crystal structure determinations. The phosphoraneiminato complex [MgBr(NPMe₃)]₄ · C₇H₈ with hetero cubane structure is formed by a metathesis reaction of [ZnBr(NPMe₃)]₄ with RMgBr (R ? Ph. Mes).     

Coordination of zwitterionic 8-quinolinol (oxine) to mixed oxinate-carboxylate complexes of divalent nickel,manganese, and magnesium

Three types of metal complexes containing coordinated zwitterionic 8-Quinolinol(oxine) are isolated from the reaction ofMOx ₂ (M=divalent Ni, Mn, or Mg; HO _x =oxine) and haloacetic acidsRCO₂H (R=CF₃, CCl₃, CHCl₂, or CH₂Cl) in benzene. These types are:M(O₂CR)Ox·HOx forM=Ni,R=CCl₃, CHCl₂, and CH₂Cl and forM=Mn,R=CHCl₂.MOx(HOx) (RCO₂)MOx·nH₂O forM=Ni, Mn, or Mg,R=CF₃ andn=1,1, and 4, respectively.MO _x (HOx) (RCO₂)₂ MOx forM=Mn andR=CCl₃. These types are compared with the simple mixed chelateMn(O₂CCH₂Cl)Ox. Interrelated reactions are suggested to explain the formation of these metal complexes and the contributing factors are discussed. The coordination of the zwitterion to the metal ion through its phenolate oxygen and the presence of the triatomic system⁺N–H...O in the three types of metal complexes are evidenced by typical infrared bands. Analytical and spectral data are in accordance with the suggested formulations.

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Koordination von zwitterionischem 8-Chinolinol (Oxin) an gemischten Oxinat-Carboxylat-Komplexen des divalenten Nickel, Mangan und Magnesium

Zusammenfassung Drei Typen von Metallkomplexen mit koordiniertem zwitterionischem 8-Chinolinol (Oxin) wurden aus der Reaktion vonMOx ₂ [M=Ni(II), Mn(II), Mg(II); HOx=Oxin] mit Halogen-essigsäurenRCOOH (R=CF₃, CCl₃, CHCl₂, CH₂Cl) in Benzol isoliert. Es werden Reaktionswege zur Bildung der Komplexe diskutiert. Die Koordination des Zwitterions über den phenolischen Sauerstoff und die Präsenz der Gruppierung⁺N–H...O in allen Typen der untersuchten Metallkomplexe wird auf Grund typischer IR-Banden nachgewiesen.

     

Zinn(IV)-Komplexe mit dreizähnigen diaciden Liganden — 119Sn-NMR und 119mSn-Mössbauer-spektroskopische Untersuchungen

Tin(IV) Complexes with Tridentate Diacidic Ligands — ¹¹⁹Sn NMR and ^119mSn Mössbauer Studies The tin(IV) chelates of tridentate diacidic azomethines of acetylacetone resp. salicylaldehyde with benzoylhydrazine, thiobenzoylhydrazine, 2-hydroxyaniline and 2-mercaptoaniline as well as with the ligands 2-(2′-hydroxy-4-methylphenyl)-6-(2″-hydroxyphenyl)pyridine, 2-(2′-hydroxyphenyl)-8-quinolinol and 2.6-diphenacylpyridine were synthesized. The compounds were characterized by IR-, UV/VIS-, MS-, ¹¹⁹Sn NMR and ^119mSn Mössbauer spectroscopy. They exist as a mixture of geometrical isomers.     

An lonophoretic study of the interactions between metal lons and 1-phenyl-3-pyrazolidinone

Summary The ionic behaviour of 1-phenyl-3-pyrazolidinone (phenidone) at different pH values and its complexes with a selected group of metal ions such as Mg(II), Al(III), Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) were investigated in the pH range of 1–13 by paper electrophoresis. pH-mobility curves were determined for phenidone, the nine metal ions and 21 metal-ligand systems with 1, 110 and 1100 metal: ligand ratios. The effect of the pH on complex formation and the influence of the phenidone concentration on the metal ion mobilities are discussed.Presented at the XXII International Conference on Coordination Chemistry, August 23–27, 1982, Budapest (Hungary).     

Synthesis, crystal structure and spectroscopic properties of two new complexes containing azido or dicyanamido bridges

Two new complexes, [Cu(L₁){N(CN)₂}]·ClO₄ (1) (L₁ is 1,8-dimethyl-1,3,6,8,10,13-hexa-azacyclotetradecane) and [Co(L₂)(N₃)₂]·ClO₄ (2) (L₂ is 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetra-azacyclotetradecane) have been synthesized and characterized. The compounds crystallize in the monoclinic system P2₁ space group for 1 and P2₁/n for 2. Single crystal X-ray analysis reveals that the compound 1 assumes a one-dimensional structure via hydrogen-bonding interactions, in which each Cu(II) ion is coordinated by four nitrogen atoms from ligand L₁ and one nitrogen atom from [N(CN)₂]⁻ anion. For compound 2, each Co(III) ion is coordinated by four nitrogen atoms of ligand L₂ and two nitrogen atoms from N₃ ⁻ anion.     

Synthesis,electrochemical and in situ spectroelectrochemical studies of new transition metal complexes with two new Schiff-bases containing N2O2/N2O4 donor groups

New Schiff-base copper and cobalt complexes, [Cu(L¹)], [Cu(L²)] and [Co(L¹)], [Co(L²)] (where L¹ = N-N′-bis(3,5-di-tert-butylsalicylaldimine)-1,4-cyclohexane bis(methylamine) and L² = N-N′-bis(3,5-di-tert-butylsalicylaldimine)-1,8-diamino-3,6-dioxaoctane), were synthesized and characterized using elemental analysis, IR spectra, UV–Vis spectra, magnetic susceptibility measurements, ¹H and ¹³C NMR spectroscopy, thermal analysis and molar conductance (Λ_M). Their electro-spectrochemical properties were investigated using cyclic voltammetric (CV) and thin-layer spectroelectrochemical techniques in a dichloromethane solution (CH₂Cl₂). The CV of [Cu(L²)] showed a lower oxidation potential than that of [Cu(L¹)] under the same experimental conditions. The oxidation wave (II) of [Cu(L²)] was accompanied by an EC process (II′), which was not observed for [Cu(L¹)]. Also, [Cu(L²)] exhibited a reduction process, but [Cu(L¹)] did not. These results indicate that the Cu(II) ion in [Cu(L²)] is coordinated by N₂O₄ donor sites while [Cu(L¹)] presents a square-planar structure with N₂O₂ donor sites. Both oxidation processes for [Co(L¹)] and [Co(L²)] are based on the cobalt center, and they are assigned to Co(II)/Co(III) couples. The spectroelectrochemical results indicate that the oxidized species of [Cu(L²)] is similar to that of [Cu(L¹)], the only difference being that the absorption bands of the oxidized species for [Cu(L²)] shift to lower energy compared with those of [Cu(L¹)] because of their different coordination environment. The geometry of [Cu(L²)] changed into square-planar after the complex was totally oxidized and the neutral complex was only recovered following the EC process, as observed from the CV of [Cu(L²)]. For the two cobalt complexes, the bands corresponding to the π → π^∗transitions disappeared and new bands with small red shifts and of lower intensity were observed during the oxidation process. These new bands are attributed to the LMCT transition as observed in the case of the oxidation processes of the cobalt complexes.     

Potentiometric studies on the complexes of tetracycline (TC) and oxytetracyclin (OTC) with some metal ions

Summary The interaction of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Zn(II), Cd(II), Hg(II), Pb(II), Al(III), and UO₂(II) ions with tetracycline (TC) were studied by potentiometricpH titrations. The formation constants of the different binary complexes formed in such systems have been determined at 25±0.1°C and =0.1 moll^–1 (NaNO₃). PotentiometricpH equilibrium measurements have been made under the same conditions for the interaction of oxytetracycline (OTC) and Cu(II), Cd(II), Pb(II), and UO₂(II). The formation of (1:1) binary complexes are inferred from the potentiometricpH tritration curves. The protonation constants ofTC andOTC were also determined under the same conditions and refined (ESAB2M computer program). The transition metal stability constants are consistent with the Irving-Williams series.

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Potentiometrische Untersuchungen der Komplexe von Tetracyclin (TC) and Oxytetracyclin (OTC) mit einigen Metall-Ionen

Zusammenfassung Die Wechselwirkungen von Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Zn(II), Cd(II), Hg(II), Pb(II), Al(III) und UO₂(II) Ionen mit Tetracyclin (TC) wurden mittels potentiometrischerpH-Titrationen untersucht. Die Komplexbildungskonstanten wurden bei 25±0.1°C und =0.1 mol/1(NaNO₃) bestimmt. Unter den gleichen Bedingungen wurden die Komplexierung von Cu(II), Cd(II), Pb(II) und UO₂(II) mit Oxytetracyclin (OTC) mittel potentiometrischerpH Gleichgewichtsmessungen untersucht. Aus den potentiometrischenpH-Titrationskurven ergab sich die Bildung von (1:1) binären Komplexen. Die Protonierungskonstanten vonTC undOTC wurden ebenfalls bestimmt und rechnerisch verfeinert (ESAB2M Computer Programm). Die Stabilitätskonstanten für die Übergangsmetalle stimmen mit der Irving-Williams Reihe überein.

     

Complex formation of hypoxanthine and 6-mercaptopurine with Cd(II) ion

Reaction of Cd(II) ion with hypoxanthine (H₂ Y) and with 6-mercaptopurine (H₂ MP) in dioxane-water (50%) leads to the formation of CdY·2H₂O and Cd(HMP)₂·2H₂O, respectively. In methanolic medium Cd(II) and H₂ MP give Cd(MP)·H₂O. These compounds have been characterized by chemical analysis, IR spectra and thermogravimetric analysis. The stability constant of CdY complex at 25±0.1 °C and 1M ionic strength with NaClO₄ in dioxane-water medium is log =10.25±0.05.

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Komplexbildung von Hypoxanthin und 6-Mercaptopurin mit Cd(II)

Zusammenfassung Die Umsetzung von Cd(II)-Ionen mit Hypoxanthin (H₂ Y) und 6-Mercaptopurin (H₂ MP) in Dioxan-Wasser (50%) ergibt die Verbindungen CdY·2H₂O und Cd(HMP)₂·2H₂O. In Methanol entsteht aus Cd(II) und H₂ MP CdMP·H₂O. Die Verbindungen wurden durch chemische Analysen, IR-Spektren und thermogravimetrische Analysen charakterisiert. Die Stabilitätskonstante der Verbindung CdY bei 25°C und bei einer Ionenstärke = 1 (NaClO₄) in Dioxan-Wasser wurde zu lg =10,25±0,05 bestimmt.

     

Mononuclear and Binuclear Fe(III), Co(II), Ni(II), and Cu(II) Complexes of 3,4′-Dihydroxyazobenzene-3′,4-dicarboxylic Acid and 3-Carboxy-4-hydroxyphenylazo-3-carboxy-4-hydroxynaphthalene

Summary. Fe(III), Co(II), Ni(II), and Cu(II) complexes of the title azodyes have been synthesized and characterized by elemental analysis, molar conductance, TGA, DTA, magnetic susceptibility measurements, IR, electronic and ESR spectral studies. The spectral studies suggest an octahedral geometry for Fe(III) and Co(II) complexes but a square planar geometry for Ni(II) and Cu(II) complexes. The kinetics of the catalysed oxidation of N,N,N,N-tetramethyl-p-phenylenediamine dihydrochloride (TMPPD) with mononuclear and binuclear copper complexes were studied to check the activity of these copper complexes in oxidizing organic amines. The electrochemical behaviour of the metal complexes was studied using DC polarography and cyclic voltammetry. Antimicrobial activity of the azo compounds and its complexes have been tested against different microorganisms.     

Indazole complexes of diorganotin(IV) dihalides. The crystal structures of dichloro and dibromodimethylbis(indazole) tin(IV)

Reaction of indazole (HInd) with diorganotin(IV) dihalides yielded compounds of the type [SnR₂X₂(HInd)₂] (R = Me, Et, Bu and Ph; X = Cl, Br). The structures of the dihalodimethylbis(indazole)tin(IV) complexes were determined by X-ray crystallography. These are trans-octahedral centrosymmetric compounds with the following bond lengths (Å) around the tin atom: Sn-Cl 2.590(2), Sn-N 2.377(6), Sn-C 2.12(1) in the chloride; and Sn-Br 2.733(1), Sn-N 2.370(5) and Sn-C 2.12(1) in the bromide. Mössbauer and vibrational spectra suggest similar trans stereochemistry for the other complexes prepared. The behaviour of these compounds in solution was studied by conductimetry and NMR techniques.