Reaction of cis-diamminedichloroplatinum(II) with arabinogalactan. The identification and therapeutic effect of the product obtained

A reaction of cis-diamminedichloroplatinum(II) with the natural polysaccharide arabinogalactan gave a product characterized by X-ray powder diffraction, IR spectroscopy, UV spectrophotometry, and thermogravimetry. It was demonstrated that cis-diamminedichloroplatinum(II) is bound to arabinogalactan by a linkage between its -C-O-C- bond and the hydrogen atom of the NH₃ group of the starting complex. The product can suppress tumor growth with no toxic effect on the organism.     

Über Chrom(II)-carboxylate und Halogenochromate(II)

Highly pure chromium(II) acetate, was obtained from chromium powder and anhydrous acetic acid in the presence of a small amount of acetylhalide. Cr^II acetate reacts with acetyl halide in anhydrous acetic acid to sesquisolvates like CrCl₂ · 3/2 CH₃COOH. If one equivalent of alkali acetate or an organic nitrogen base is added to solutions of Cr^II acetate in acetyl halide/acetic acid mixtures, trihalochromates(II) are precipitated which are hexagonal in structure, except the ammonium and the potassium salt. With two equivalents of alkali or ammonium acetate tetrachlorochromates(II) of cesium, rubidium and ammonium are precipitated. They are tetragonal in structure (K₂NiF₄ type). Using pyridinium acetate with various mixtures of acetyl bromide and acetic acid, only the solvates (PyH)₃(CrBr₅) · 2CH₃COOH is formed.     

Separation of alkaline earth elements by cation-exchange chromatography in ammonium malonate media

Be(II), Mg(II), Ca(II), Sr(II) and Ba(II) can be separated by elution from a cation-exchange column in the ammonium form with increasing concentrations of ammonium malonate. A typical elution sequence for a 60-ml column (volume in H⁺-form) of AG₅₀-X8 resin is: 200 ml of 0.20 N ammonium malonate plus 0.10 N malonic acid for Be(II); 300 ml of 0.50 N, 450 ml of 0.70 N, 350 ml of 1.10 N ammonium malonate for Mg(II), Ca(II) and Sr(II), respectively, and 200 ml of 3.0 N nitric acid for Ba(II). Separations are sharp and quantitative for element pairs in weight ratios from 1:1000 to 1000:1. Distribution coefficients, elution curves and quantitative separations are presented.     

(E) Enol ethers from the stereoselective reduction of α-alkoxy-β-ketophosphonates and Wittig type reaction

When α-alkoxy-β-ketophosphonates, prepared by the Rh(II) mediated insertion reaction of α-diazo-β-ketophosphonates into the OH bond of primary alcohols, were reduced either by NaBH₄ in the presence of CaCl₂ or by DIBAL, they respectively gave the corresponding anti or syn stereomeric hydroxyphosphonates with pronounced to complete stereoselectivity. Submitted to the action of potassium tert-butoxyde, syn isomers led to the corresponding pure (E) enol ethers in moderate to good yields. Under the same conditions anti isomers led to a mixture of (Z) and (E) enol ethers in rather poor yields. The sequence was applied to the preparation of some allyl-vinyl ethers with a (E) configuration for the vinylic double bond.     

(N,N-dimethylbenzylamine-2C,N)palladium(II) and -platinium(II) β-diketonates and thio-β-diketonates

(N,N-dimethylbenzylamine-2C,N)palladium(II) and -platinum(II) β-diketonates, DmbaML, have been synthesized by reaction of [DmbaMCl]₂ with the free ligand and KOH, or with the thallium(I) salt of the ligand. The various isomers formed have been investigated by ¹H and ¹⁹F NMR spectroscopy. Infrared and mass spectroscopic studies have also been made on the compounds.     

Studies in the tetraarylborates : The preparation and reagent properties of sodium tetrakis(p-chlorophenyl)borate

Sodium tetrakis(p-chlorophenyl)borate was synthesized. It formed precipitates with K⁺, Rb⁺, Cs⁺, quarternary ammonium and protonated basic nitrogen compounds. The potassium salt was more soluble than potassium tetraphenylborate but flocculated more readily and filtered more easily. The salts formed with nitrogen compounds offer possibilities as derivatives suitable for qualitative analysis.     

Distribution coefficients of vitamin B2 in hydrophilic organic solvent-aqueous salt solution systems

Distribution coefficients of vitamin B₂ in hydrophilic solvent (n-butanol, isopropanol, acetone, ethyl acetate, and their mixtures)-aqueous salt (potassium chloride, sodium fluoride, and ammonium sulfate salting-out agents) solution systems were calculated. The synergic effect and optimum proportions of components in the solvent mixture for efficient extraction of vitamin B₂ from aqueous solutions were established.     

Bis(diisopropylammonium) thiosulfate and bis(tert‐butylammonium) thiosulfate

Two new dialkylammonium thiosulfates, namely bis(diisopropylammonium) thiosulfate, 2C₆H₁₆N⁺·S₂O₃²⁻, (I), and bis(tert‐butylammonium) thiosulfate, 2C₄H₁₂N⁺·S₂O₃²⁻, (II), have been characterized. The secondary ammonium salt (I) crystallizes with Z = 4, while the primary ammonium salt (II), with more hydrogen‐bond donors, crystallizes with Z = 8 and a noncrystallographic centre of inversion. In both salts, the organic cations and thiosulfate anions are linked within extensive N—H...O and N—H...S hydrogen‐bond networks, forming extended two‐dimensional layers. Layers are parallel to (10) in (I) and to (002) in (II), and have a polar interior and a nonpolar hydrocarbon exterior. The layered structure and hydrogen‐bond motifs observed in (I) and (II) are similar to those in related ammonium sulfates.     

EPR and electronic spectroscopic studies of Keggin type undecatungstophosphocuprate(II) and undecatungstoborocuprate(II)

The coordination of Cu(II) to the Keggin type anions α-undecatungstophosphocuprate(II) and α-undecatungstoborocuprate(II) was investigated in different environments by EPR and electronic spectroscopy. This study has shown that the coordination geometry around Cu(II) in the tetrabutylammonium (TBA) salts, (TBA)₄H_x[XW₁₁CuO₃₉], with X=P or B, is square pyramidal, with copper bound to the five oxygen donor atoms of the polyoxometalate, whereas for the [XW₁₁Cu(H₂O)O₃₉]ⁿ⁻ anion, on the corresponding potassium salt, a tetragonally elongated pseudo-octahedral geometry was found. For the potassium salts, in aqueous solution, six-coordinated copper is the only form found. For the TBA salts, in nonaqueous solvents, we can observe either the presence of only one form (the six-coordinated Cu(II) species, with a solvent molecule bound to copper), or of two forms: the solvent coordinated copper anions and the five-coordinated copper [XW₁₁CuO₃₉]ⁿ⁻ anions.     

KI与无机铵盐催化CO2与环氧丙烷合成碳酸丙烯酯

以无毒、合成简单、廉价的无机铵盐(氨基甲酸铵、碳酸氢铵、碳酸铵等)为助催化剂, 研究其对卤化钾(KCl、KBr、KI)催化CO₂与环氧丙烷合成碳酸丙烯酯(PC)的影响. 结果表明, 卤化钾与无机铵盐显示出很好的协同催化效应. 其中以氨基甲酸铵为助催化剂, KI为主催化剂时, 催化合成PC的效果最好. 同时考察了催化剂用量、反应温度、CO₂初始压力、PC的预加入量、反应时间等因素对反应的影响. 在优化条件下, PC收率大于99%.     

Preparation of 1,3-dienyl organotrifluoroborates and their Diels-Alder/cross-coupling reactions

2-BF₃-substituted 1,3-butadienes with potassium and tetrabutyl ammonium counterions have been prepared in gram quantities from chloroprene via a simple synthetic procedure. The potassium salt of this new main group element substituted diene has been characterized by ¹H, ¹³C, ¹¹B, and ¹⁹F NMR and the tetra n-butyl ammonium salt was also characterized by X-ray crystallography. Diels-Alder reactions of these dienes with dienophiles such as ethyl acrylate, methyl vinyl ketone, and N-phenylmaleimide are reported as well as subsequent Pd-catalyzed cross-coupling reactions of those Diels-Alder adducts. 4-Phenyl-2-BF₃-substituted 1,3-diene was prepared by magnesium-halogen exchange from the corresponding 2-bromo and iodo dienes. The 4-phenyl-2-bromo-1,3-butadiene was also characterized by X-ray crystallography. 4-Phenyl-2-BF₃-1,3-butadiene was used in Diels-Alder/cross-coupling reactions and the product of a Diels-Alder reaction with N-phenylmaleimide followed by cross-coupling with 4-bromo-benzonitrile was also characterized by X-ray crystallography.     

Complexometric estimation of copper

Summary Copper(II) or Copper(II) and iron(III) in a mixture are determined by titration with EDTA (disodium salt) solution as complexometric reagent at p_H 4.0 using potassium thiocyanate-p-anisidine as an indicator.Fe^III is estimated in the mixture by titration with EDTA (disodium salt) solution using potassium thiocyanate-ether as an indicator.Cu^II present in the mixture is, therefore, equivalent to the difference in amounts of the EDTA (disodium salt) used for the two sets of titrations of the mixture using potassium thiocyanate-p-anisidine and potassium thiocyanate-ether as indicators respectively.Strontium, magnesium, manganese, calcium, barium and mercuric ions do not interfere in these estimations.

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Zusammenfassung Kupfer(II) oder Kupfer(II) und Eisen(III) zusammen werden komplexometrisch mit ÄDTA-Lösung bei p_H 4,0 unter Verwendung von Kaliumthiocyanat-p-Anisidin als Indicator titriert. Eisen(III) wird in dem Gemisch durch komplexometrische Titration gegen Kaliumthiocyanat-Äther als Indicator bestimmt. Der Kupfer(II)-gehalt ergibt sich aus der Differenz der beiden Titrationen. Strontium, Magnesium, Mangan, Calcium, Barium und Quecksilber(II) stören nicht.

     

Solvent-induced chirality switching in the enantioseparation of regioisomeric hydroxyphenylpropionic acids via diastereomeric salt formation with (1R,2S)-2-amino-1,2-diphenylethanol

The enantioseparation of three hydroxyphenylpropionic acid isomers via diastereomeric salt formation with (1R,2S)-2-amino-1,2-diphenylethanol has been demonstrated. The racemates of all three acid isomers were successfully separated with high efficiency (0.56–0.84) after single crystallization. For 2-hydroxy-3-phenylpropionic acid 4, the configuration of the less-soluble salt was controlled by the crystallization solvent: the (R)-4 salt was crystallized from water, while 2-propanol afforded the (S)-4 salt. The chiral recognition mechanism of the three acids was discussed based on the crystal structures of the diastereomeric salts.     

High Performance Liquid Chromatography of Uroporphyrin Isomers

Abstract

The separation of uroporphyrin I and III isomers by reversed-phase high performance liquid chromatography on ODS-Hypersil with ammonium acetate buffer-acetonitrile solvent systems is described. The effects of buffer concentration, pH, organic modifier proportion and different organic modifiers on the resolution are studied. The optimum conditions for the separation were 12–13% acetonitrile in 1M ammonium acetate buffer pH 5.10–5.20. The method also separated uroporphyrin I and III from the II isomers but the resolution of uroporphyrin III and IV isomers was not achieved.     

Diagnostic features for the linkage isomerism of the oximato group: Characterization of some Cu(II), Co(II) and U(VI) complexes of a dioxime schiff-base ligand

The reactions of the dioxime ligand N,N'-ethylenebis(isonitrosoacetylacetoneimine) with Cu(II), Co(II) and U(VI) ions produced metal complexes with the oximato groups coordinated through both oxygens, both nitrogens or one oxygen and one nitrogen. Some interconversion of isomers was observed. The U(VI) complexes reacted with Ni(II) acetate to produce the Ni(II) analogue of the Cu(II) complex with the oxygen coordination isomer. The observed linkage isomerism of the oximato group and the suggested formulations of the metal complexes are based on analytical, electronic and vibrational spectra, and magnetic-moment evidence.     

Derivatographic studies on dehydration of salt hydrates and their deuterium oxide analogues. V

Non-isothermal thermal studies of the dehydration of the double salt hydrates of the type M(I)₂SO₄·M(II)SO₄·6H₂O and their D₂O analogues were carried out where M(I) = TI(I) and M(II) = Mg(II), Co(II), Ni(II), Cu(II) or Zn(II). Thermal parameters like activation energy, order of reaction, enthalpy change, etc. were evaluated from the analysis of TG, DTA and DTG curves. These thermal parameters were compared with those of other series, like NH₄(I), K(I), Rb(I) and Cs(I) studied earlier. On deuteration the nature of dehydration altered in the case of Tl₂Zn(SO₄)₂·6H₂O only. The thermal stability of the salt hyd discussed in relation to the salt hydrates of other series. The role of divalent cation on the thermal properties of dehydration of salt hydrates is also discussed. The order of reaction was always found unity. The values of ΔH were within ≈12–≈16 kcal mol^?1.     

SYNTHESIS OF 1,4,7,10-TETRA-N-ALKYL-1,4,7,10-TETRAAZA-CYCLODODECANES

ABSTRACT

We report a concise method for the preparation of 1,4,7,10-tetra-N-alkyl-1,4,7,10-tetraaza-cyclododecanes via deprotonation to the fourfold lithium amide followed by alkylation with alkyl bromides. The procedure circumvents the problem of ammonium salt formation and provides direct access to hydrophobic 1,4,7,10-tetraaza-cyclododecanes in moderate yield. The so obtained hydrophobic macrocycles were converted into the corresponding zinc(II), copper(II), nickel(II) and cobalt(II) complexes, that may be used as water stable Lewis-acids in catalysis and anion extraction.     

Separation and Column Performance of Certain Radiotracers Using a Chromatographic Column of Celite Loaded with Adogen-381 and Selected Eluents

Abstract

The radiotracers Mo(VI), Sc(III), Ce(III), Eu(III), Tm(III). Fe(III), Hg(II), Cd(II), Zn(II), Cu(II) and Co (II) could be separated from each others using a hydrophobic celite column coated with Adogen-381 together with the mobile phases hydrochloric acid, nitric acid, potassium thiocyanate, ammonium acetate or water. The elution behaviour was satisfactorilly interpreted. The effect of the flow rate (50–300 ul/min) and temperature (26–70°C) on the column performance of Co(II) was also studied.     

An ion-exchange scheme for the determination of the major cations in sea water

A cation-exchange scheme is described for the determination of the principal cations in sea water. The cations are adsorbed onto a column of Amberlite CG 120. Sodium and potassium are eluted together using 0.15 M ammonium chloride and determined gravimetrically as sulphates; potassium is then determined gravimetrically as potassium tetraphenylboron and sodium is determined by difference. Magnesium and calcium are eluted by means of 0.35 M ammonium chloride and 1 M ammonium acetylacetonate (pH 9.6) respectively, and titrated with EDTA. Finally, strontium is eluted with 2 M nitric acid and determined by flame photometry. Tests made using an artificial sea water showed that the method had coefficients of variation of 0.02, o.22, 0.04, 0.08 and 0.8% for sodium, potassium, magnesium, calcium and strontium respectively.     

Bis(1‐phenyl­ethyl­ammonium) hexa­chloridostannate(IV) and bis­(2‐phenyl­ethyl­ammonium) hexa­chloridostannate(IV)

The crystal structures of the two isomers bis­(1‐phenyl­ethyl­ammonium) hexa­chloridostannate(IV) and bis­(2‐phenyl­ethyl­ammonium) hexa­chloridostannate(IV), both (C₈H₁₂N)₂[SnCl₆], exhibit alternating organic and inorganic layers, which inter­act via N—H⋯Cl hydrogen bonding. The inorganic layer contains an extended two‐dimensional hydrogen‐bonded sheet. The Sn atom in the 1‐phenylethyl­ammonium salt lies on an inversion centre.