A 31P NMR STUDY OF TERTIARY PHOSPHINE COMPLEXES OF PLATINUM(II) AND PALLADIUM(II)

Complexes of the type NBu ₄ MCl ₃ PR ₃ R=P.Tolyl,Ph,Bu) (M = Pt, Pd) are prepared by the reaction of MCl ₂ or K ₂ [MCl ₄ ] by phosphine ligands. Addition of NBu ₄ Br or NBu ₄ I to these compounds, in dichloromethane results in a redistribution of halogens and formation of all six isomers of the type MBr _{3 ?X}Cl_XPR ₃ X= 0, 1, 2, and 3 which have been identified by ³¹ P- ¹ H NMR spectroscopy. The intensities show that the products are proportional to the statistical distribution.     

COMPLEXES OF AMINOPHOSPHONATES PART 9.1 COPPER(II) COMPLEXES OF CIT RIC ACID DERIVATIVES

Abstract

Complex formation between copper(II) and 3-amino-3-phosphonoglutaric acid (Apga), an ambidentate aminophosphonate or citric acid derivative, was studied in aqueous solution by pH-potentiometry and EPR and electronic spectroscopy. Complexation with the parent molecules citric acid and tricarballylic acid was reinvestigated. The stoichiometries and stability constants of the complexes formed in these systems were determined at 25°C at an ionic strength of 0.20 mol dm^?3 (KCl). Stability constant data and spectroscopic results revealed that in the acidic pH range Apga behaves as a citric acid derivative, forming the phosphonate-bridged dimeric species Cu₂A₂H₂, while in the basic pH range, with decreasing proton competition at the amino binding site, it rearranges to yield mononuclear complexes involving aminophosphonate-like (NH₂, PO₃ ^2-, CO₂) coordination.     

DECARBONYLATION OF ACYLCHLOROBIS-(TRIPHENYLPHOSPHINE) PLATINUM(II) COMPLEXES PROMOTED BY TIN(II) CHLORIDE

Abstract

While it might be expected that the availability of vacant coordination sites in the four coordinate acyl complexes trans[Pt(PPh₃)₂ (RCO)Cl] provides low energy pathways for alkyl and aryl migration and subsequent decarbonylation, the decarbonylation has been previously achieved only at elevated temperatures. The addition of SnCl₂ greatly facilitates decarbonylation of [Pt(PPh₃)₂ (RCO)Cl] where R is CH₃, C₂ H₅, Y[sbnd]C₆ H₄. Compounds of the type [Pt(PPh₃)₂ (RCO)SnCl₃] and [Pt(PPh₃)₂ R(SnCl₃)] have been isolated. The removal of SnCl₂ from these compounds has been achieved with ethanol. A kinetic study of the decarbonylation of [Pt(PPh₃)₂ (RCO)SnCl₃] (where R is CH₃, C₂ H₅, Y[sbnd]C₆ H₄ for Y=H, CH₃, CH₃ O, NO₂, Cl) is reported. The role of 3 and 5 coordinate intermediates in alkyl-aryl migrations in Pt(II) systems is discussed.     

COMPLEXES OF BINUCLEATING LIGANDS. X. SOME COPPER(II), NICKEL(II), PALLADIUM(II), AND PLATINUM(II) COMPLEXES OF SULPHUR-CONTAINING LIGANDS

Abstract

Copper(II) and nickel(II) complexes of the trianionic binucleating ligand (R^3-) derived from 4-hydroxy-bis-3,5-[N-(S-methyl-dithiocarbamate) formimidoyl]toluene have the general form RM₂(Z) where Z represents a range of monoanionic bridging species. Palladium(II) and platinum(II) complexes formed by R^3- and the related trianionic ligands derived from 2-hydroxy-5-methylisophthalaldehyde di-2′-mercaptoanil and 2-hydroxy-5-methylisophthalaldehyde dithiosemicarbazone have the 2:1 formulation [(ligand)M₂(Z)] only when the bridging species, Z, coordinates strongly enough to give the binucleating ligand substantial assistance in maintaining the binuclear structure. In the absence of a ‘good’ bridging group and in the presence of pyridine, 3:2 complexes of the form [(ligand)₂ M₃ (pyridine)₂] (where M = Pd, Pt) are produced in which the binucleating ligand fails to bind the two metals in close proximity.     

A NOVEL SERIES OF PALLADIUM(II) AND PLATINUM(II) COMPLEXES WITH 1,4-BENZODIAZEPINES AS LIGANDS

Abstract

The complexing behaviour towards palladium(II) and platinum(II) halides of some 1,4-benzodiazepines is reported. The ligands used in this study are 7-chloro-2-methylamino-5-phenyl-3H-1,4-benzodiazepin-4-oxide, 1,3-dihydro-7-nitro-5-phenyl-2H-1,4-benzodiazepin-2-one and 7-chloro-1-methyl-5-phenyl-3H-1,4-benzodiazepin-2-one. The complexes have been studied by means of magnetic susceptibility measurements, infrared and far infrared spectra, electronic spectra and conductivity measurements. The most convincing structural evidence for these complexes is a square planar stereochemistry with bridging ligands joining two metal ions and terminal halides in the 1:1 complexes and terminal ligands and terminal halides in the 1:2 derivatives. Assignments for the metal-ligand and metal-halide bands have also been made.     

NOTE: SYNTHESIS OF Cu(II) AND Zn(II) COMPLEXES WITH SCHIFF BASE DERIVATIVES OF 2-ACETYLPYRROLE

Abstract

Bis chelate complexes of Cu(II) and Zn(II) were synthesized with methylamine and ethylamine Schiff base derivatiies of 2-acetylpyrrole. Stable complexes were obtained, with the exception of the Cu(II) ethylamine adduct. which slowly hydrolyzed in air to yield a mixed ligand product containing one ethylamine Schiff base and one 2-acetylpyrrole per metal centre. The instability of the bis Cu(II) ethylamine Schiff base complex with respect to stable Cu(II) methylamine and Zn(1I) ethylamine complexes is discussed.     

THE SYNTHESIS OF TRISELENOCARBONATE COMPLEXES OF PLATINUM

The addition of dichloromethane solutions of carbon diselenide to liquid ammonia containing suspensions of platinum bis-phosphine dichlorides [PtCl₂(PR_X)_n] (n = 2, (PR_X) = PMe₃, PMe₂Ph, PMePh₂, and PPh₃, n = 1, (PR_X) = dppm, dppe, dppp, dppf) gives, after evaporation of the ammonia and extraction of the reaction residues with dichloromethane, the appropriate platinum bis-phosphine triselenocarbonate complexes in reasonable yields (40–60%).     

高效液相色谱法研究铂(Ⅱ)配合物的配体交换反应

本文用高效液相色谱法研究了[Pt(TMDACP)I_2]和[Pt(TMDACP)(Cl-Ac)_2](TMDA是1,2,2-三甲基-1,3-二氨基环戊烷,Cl-Ac是氯乙酸根)的配体交换反应,测得20±0.1℃二级速率常数和平衡常数分别为(8.67±0.37)×10~(-3)mol~(-1)dm~3s~(-1)和0.572±0.008。     

REPARATION AND CHARACTERIZATION OF NEW SUPROFEN COMPLEXES OF Fe(III), Co(II) AND Ni(II)

Abstract

The preparation and properties of new complexes containing the biometals Fe(III), Co(II) and Ni(II) coordinated to the anti-inflammatory drug Suprofen are reported. The elemental analyses, together with the magnetic and thermal behavior and electronic, IR and Raman spectra, indicated the following stoichiometries for the latter two complexes: [M(Sup)₂(H₂O)₄]. For the Fe(III) complex, the generation of a dinuclear species may be proposed on the basis of ⁵⁷Fe Mössbauer measurements.     

DIPHENYLANTIMONY(III) DERIVATIVES OF ALKYL XANTHATES

Abstract

A few diorganoantimony(III) derivatives, Ph₂SbS₂COR, have been prepared by the interaction of Ph₂SbCl/Ph₂SbOAc with ROCS₂ K (where R ? CH₃, C₂H₅, n-C₃H₇, i-C₃H₇, n-C₄H₉, i-C₄H₉). These derivatives have been characterized by elemental analyses, molecular weight determinations, IR and NMR (¹H and ¹³C) spectral data. The monodentate nature of the ligand in these derivatives has been proposed.     

SYNTHESIS AND CHARACTERIZATION OF Fe(III), Co(III), Cu(II) AND Zn(II) COMPLEXES OF N-2,4-HYDROXYBENZAL-D-GLUCOSAMINE

Abstract

The Schiff base N-2,4-dihydroxybenzal-D-glucosamine (L), and its Fe(III), Co(III), Cu(II) and Zn(II) complexes have been synthesized and characterized. Magnetic moments suggest that all complexes are high-spin. The Cu(II) chelate in DMF solution has a distorted tetrahedral structure, as shown by ESR and electronic spectra. Detailed studies have been made concerning the solution equilibrium of L with transition metal ions. Stabilities of the complexes are in accord with the Irving-Williams series.     

STUDIES ON THE BACTERIAL ACTIVITY OF COBALT(III) COMPLEXES. PART III. COBALT(III) CARBOXYLATE COMPLEXES

Abstract

Cobalt(III) complexes of the type [Co(en)₂(chel)]X.nH₂O where en = ethylenediamine, chel = phthalato = C₆H₄CO₂)^2? ₂, maleato = (O₂CCH = CHCO₂)^2?, succinato = (O₂CCH₂CH₂CO₂)^2?, homophthalato = (O₂CC₆H₄(CH₂)CO₂)^2?, citraconato = (O₂CC(CH₃) = CHCO₂)^2?, itaconato = (CH₂ = C(CO₂)CH₂CO₂)^2?, X = NO^? ₃, Br^?, (O₂CC₆H₄CO₂H)^?, (O₂CHC = CHCO₂H)^?, (O₂C(CH₂)₂CO₂H)^?, (O₂CC₆H₄(CH₂)CO₂H)^?, (O₂CHC = C(CH₂)-CO₂H)^?, and (O₂C-CH₂?C(= CH₂)-CO₂H)^?, [Co(en)₂(malonato)]X.2H₂O (where malonato = (O₂CCH₂CO₂)^2?, X = Cl^?, Br^?, and NO^? ₃) and [Co(en)₂CO₃]Cl.2H₂O have been investigated for their bacterial activity against Escherichia coli B growing on EMB agar and in minimal glucose media both in lag and log phases. Among the most active are where chel = phthalato and homophthalato. The effects are distinct from those known for compounds of Pt, e.g., cis?[Pt(NH₃)₂Cl₂] and rhodium, e.g., trans?[Rh(C₅H₅N)₄,Cl₂].6H₂O. Antagonisms are reported.     

KINETICS OF THE CHROMIUM(II) REDUCTIONS OF CHELATED AMINO ACIDO-BIS(ETHYLENE-DIAMINE)COBALT(III) COMPLEXES

Abstract

The kinetics of Cr²⁺(aq) reductions of glycinato-, D,L-alanato, D,L-phenylalanato-, and D,L-leucinatobis-(ethylenediamine)cobalt(III) ions have been investigated. The rate law is of the form d(ln[Co(III)]/dt = k[Cr²⁺], where the rate constant k(M^?1sec^?1) and associated activation parameters δH^δ(kcal mol^?1 and δS^δ (cal deg ^?1mol^?1) in parentheses, are respectively 1.65 · 0.06 (9.7 · 0.1, -25 · 1), 0.367 · 0.008 (10.9 · 04,-24 ·1), 0.529 · 0.021 (11.2 · 0.4, -22 · 1); and 0.358 · 0.019 (11.5 · 0.3, -22 · 1) at 298^·K and ·[CIO·] = 1.0 M. The reactions are all inner-sphere.     

多齿铂配合物的合成和NMR研究

本文制备了一些新的铂配合物cis-PtA_2X_2,式中A为NH_3,i-prNH_2;X_2H_2为天冬酸,硫代二乙酸和N-烷基亚胺二乙酸,并用~1H,~(13)CNMR和IR技术研究了不同条件下配体与铂的配位方式。数据表明,硫代二乙酸以S,O,O方式;天冬酸以N,O方式与铂配位,而N-烷基亚胺二乙酸可以N,O(pH>5.5)或N,O,O(pH<4)两种不同方式与铂配位。同时考察了某些配合物在水中的稳定性。     

非经典铂类抗癌配合物的进展近况

介绍了非经典铂类抗癌配合物的发展概况,并按中心离子价态、配体及配合物结构特征对其进行分类,讨论其构效关系,对新的铂类抗癌药物的研制具有一定的指导意义     

金和铂的某些冠醚类配合物的合成与性质

制得5种金和铂的冠醚类配合物,用元素分析、红外和紫外光谱、摩尔电导和~1H核磁共振谱等方法研究了配合物的组成及其有关性质。     

COMPLEXES OF Al(III) WITH HYDROXYAROMATIC LIGANDS

Abstract

In order to assess the aluminium binding ability of humic and fulvic acids, important organic soil constituents, a pH-potentiometric study was made of the proton and aluminium(III) complexes of various bi-, tri- and tetradentate catechol and salicylic acid derivatives at 25°C and at an ionic strength of 0.20moldm^?3 (KC1). The stability data revealed that at low pH the salicylate function, and at high pH the catecholate function, is preferentially bound to the aluminium ion. In the intermediate pH range, mixed hydroxo complexes and other di/oligomeric species are also formed. With an increase of the number of available coordinating sites in the molecule, the tendency to oligomeric complex formation increases, while the tendency to metal ion hydrolysis decreases.     

COMPLEXES OF GALLIUM(III) WITH HYDROXYAROMATIC LIGANDS

Abstract

The equilibria between gallium(III) ion and selected hydroxyaromatic and dihydroxyaromatic ligands at 25°C, μ=0.100 M (KNO₃) have been determined. Potentiometric measurements on 1:1, 2:1, and 3:1 molar ratios of ligand to Ga(III) have been made as a function of degree of neutralization over the entire accessible ?log [H⁺] scale. Calculations were carried out so as to take account of competing hydrolytic reactions, and formation constants of gallium(III) with chromotropic acid, 8-hydroxyquinoline-5-sulfonic acid, 5-sulfosalicylic acid, and 1,2-dihydroxy-benzene-3,5-disulfonic acid were obtained. Stable hydroxo chelates do not form under the reaction conditions employed. The protonation constants of the ligands and the formation constants of the gallium chelates are discussed and compared with previously published work on these gallium chelates and on chelates of “analogous” metal ions such as those of Fe(III) and A1(III).     

UNSYMMETRICAL TETRADENTATE COMPLEXES OF COPPER (II)

Abstract

Four mixed tetradentate Cu(II) chelates were prepared by reacting a copper salt, acety acetone, and ethylene-diamine with salicylaldehyde, o-hydroxyacetophenone, o-hydroxypropiophenone, and o-hydroxybutyrophenone, respectively. The I.R., optical, and E.S.R. spectra were obtained and discussed with regard to the expected bonding changes and/or those predicted by a model molecular orbital calculation for mixed ligand complexes.