Platinum Halide Complexes Research Articles

Regularities of Ion-Exchange Extraction of Anions 2(4)-Octylaminopyridines from Aqueous Media

Purpose of the study. Based on the results of the study of salts of 2(4)-octylaminopyridines (2(4)-OAP) by physical methods and their distribution in the two-phase system water-chloroform, establish the patterns of ion-exchange extraction of anions using aromatic amines.Methods. Chemical synthesis of 2(4)-OAP and their halides, spectrophotometry to determine the concentration of 2(4)-OAP in the aqueous and organic phase, characterization of 2(4)-OAP and their halides by IR, PMR and ESCA spectroscopy.Results. Synthesized by original methods and identified 2(4)-OAP and their halides. The distribution constants of 2-aminopyridine and 4-OAP salts with a singly charged anion in the water–chloroform two-phase system were determined. It is shown that the obtained constants increase in the following order: F-<Сl-<NO3-<Br-<ClO4-<SCN-<I-. In this case, a linear correlation between the logarithms of the constants and the hydration energy of anions in thisseries as a whole, which is typical for extraction with aliphatic amines and quaternary ammonium bases (FABs), is not observed. The results of the study of 2(4)-OAP halides by physical methods indicate a redistribution of the electron density in the aromatic cation depending on the nature of the anion, which ensures the selectivity of the extraction of “soft” (according to Pearson) 2(4)-OAP anions from aqueous media.Conclusion. The patterns of anion-exchange extraction of 2(4)-OAP, as well as, apparently, other aromatic amines, on the one hand, and aliphatic amines and PAO, on the other hand, coincide only with respect to “hard” anions. The situation changes during the extraction of "soft" anions. Due to the specificity of interionic interaction, aromatic amines are more selective with respect to "soft" anions, including, apparently, some acid complexes of "soft" metal cations, for example, with respect to halide complexes of platinum and other rare metals that are extracted by 2(4)-OAP better than by aliphatic amines and PAO.

Parallel Implementation of the Four-Component Relativistic Quasidegenerate Perturbation Theory with General Multiconfigurational Reference Functions.

A new, efficient parallel algorithm for four-component relativistic generalized multiconfigurational quasidegenerate perturbation theory (GMC-QDPT) introducing Kramers symmetry is implemented. Because it utilizes the independence of the terms in the matrix element computations, this algorithm both speeds up the calculation and reduces the computational resources required for each node. In addition, the amount of memory for two-electron integrals is reduced to three-eigths by Kramers restriction. The algorithm is applied to the d-d excitation energies of the platinum halide complexes, [PtCl4](2-), [PtBr4](2-), and [PtCl6](2-) and to the 6p-7s and 6p-7p excitation energies of the radon atom. It is shown to provide high parallelization efficiency and accurate excitation energies that agree well with experimental data.

Theoretical studies on vibrational spectra of mixed cyanide–halide complexes of platinum(IV) and palladium(IV)

The vibrational spectra of mixed cyanide–halide complexes, M(CN) 4X 2 2− and M(CN) 5X 2− (M=Pt and Pd; X=F, Cl, Br and I), have been systematically investigated by ab initio RHF, B3LYP and MP2 methods with LanL2DZ and SDD basis sets. The calculated vibrational frequencies of platinum complexes are evaluated via comparison with the experimental values. In the infrared frequency region, the CN stretching vibrational frequencies calculated at B3LYP level with two basis sets are in good agreement with the observed values with deviations, −16–4 cm −1 for Pt(CN) 4X 2 2− and −18 to −2 cm −1 for Pt(CN) 5X 2−. However, in far-infrared region, the results obtained at RHF level are better than those calculated at B3LYP and MP2 levels. For RHF/SDD method, the deviations for PtX and PtC stretching vibrational frequencies are −14–1 and −12 to −2 cm −1 in the complex Pt(CN) 4X 2 2−, −19 to −11 and −15–14 cm −1 in the Pt(CN) 5X 2− complex, respectively. The vibrational frequencies of palladium(IV) and some platinum(IV) complexes that have not been experimentally reported are predicted.

Theoretical Study of Far-Infrared Spectra of Some Palladium and Platinum Halide Complexes

The far-infrared spectra of palladium and platinum halide complexes, MX42- and M2X62-, have been studied for the first time using ab initio restricted Hartree−Fock method with the LANL2DZ basis set. The calculated vibrational frequencies, scaled with a uniform factor of 1.12, are in good agreement with the measured values. Moreover, some vibrational frequencies are predicted for palladium and platinum complexes that are difficult to measure.

Synthesis and electrospray mass spectrometry of platinum(II) complexes derived from thiourea dianions and the x-ray structure of [Pt{NMeC(=NCN)S}(COD)] (COD = CYCLO-OCTA-1,5-DIENE)

Platinum(II) complexes formally derived from the thiourea dianion [MeNC(S)N(CN)] 2 have been synthesized from the platinum-halide complexes cis-[PtCl 2L 2] [L = tertiary phosphine or L 2 = cyclo-octa-1,5-diene (COD)] by reaction with the sodium salt of N-methyl N-cyanothiourea. The complexes have been fully characterized, including an X-ray crystal structure determination of [Pt{NMeC(=NCN)S}(COD)]. The results of an electrospray mass spectrometry study on platinum(II) complexes of thiourea dianions are also reported, including the in situ coordination chemistry with silver(I) ions. Copyright © 1996 Elsevier Science Ltd

Spectroscopic studies of hydrated cyano and cyano–halide complexes of platinum (starting materials for the preparation of one-dimensional conductors)

Infrared studies from 4000–80 cm−1 were conducted on various hydrates of cyano and cyano–halide complexes of Pt(II) and Pt(IV). Tentative assignments for the vibrations involving the Pt atom, and for the water modes, were made. The latter assignments were based on a comparison with deuterated salts. Comparisons of the results obtained for these starting materials used in the preparation of one-dimensional electrical conductors, with those of the conductors themselves are given.

Transition metal–carbon bonds. Part XXXVI. Internal metallations of platinum–dimethyl(1-naphthyl)phosphine and –dimethyl(1-naphthyl)arsine complexes and attempts to effect similar reactions with palladium

A number of complexes of the types [MX2{EMe2(1-naphthyl)}2](M = Pt or Pd; X = Cl, I, or Me; E = P or As, are described). The platinum halide complexes showed no tendency to undergo internal metallation reactions even on prolonged heating but the methyl analogues (X = Me) readily evolved methane on pyrolysis to give complexes in which the naphthyl group had been metallated in the 8-(peri-) position. In the presence of sodium acetate, however, the platinum halide complexes readily give metallated derivatives, e.g. cis- or trans-[PtCl2L2](L = PMe2C10H7) gives [PtCl(P–C)L] where (P–C) the peri-metallated phosphine (L). We were unable to metallate the palladium complexes, either decomposition occurred or starting material was recovered. 1H N.m.r. data are given. The resonances of protons at positions 2 and 3 for complexes of types cis-[MX2(EMe2C10H7)2] absorb at abnormally high τ-values (3–4); an explanation for which is given.

Inhibition of leucine aminopeptidase and malate dehydrogenase by aquoplatinum (II) complexes

Halide complexes of platinum have been previously shown to inhibit tumors and cell growth as well as to possess immunosuppresive activity. Evidence is presented here that the active species in Rb 2PtBr 4 solutions which inhibits both leucine aminopeptidase ( l-leucyl-peptide hydrolase, EC 3.4.1.1) and malate dehydrogenase ( l-malate:NAD + oxidoreductase, EC 1.1.1.37) enzymes is PtBr 3(H 2O) −. The aquo complex earlier has been shown to be in equilibrium with PtBr 4 2− in solution and the rate of formation is known. This is in accord with the rate of inhibition of enzyme activity by fresh solutions of Rb 2PtBr 4. This reagent should provide another method for studying the active site and function of enzymes.

Inhibition of leucine aminopeptidase by halide complexes of platinum.

Inhibition of leucine aminopeptidase by halide complexes of platinum.

Interaction between organomercurials and halide complexes of platinum, palladium, and nickel. Carbon monoxide insertion into the platinum–carbon bond

The reactions between R12Hg (R1= Ph or Me) and (R23P)2MCl2(M = Pt, Pd, or Ni) to yield R1HgCl and trans-(R23P)2MR1Cl have been examined. The reactions with R1= Ph proceed more readily than those with R1= Me. Reverse reactions between HgCl2 and (R23P)2MR12 produce the same products.R12Hg and the carbonyl complexes (R23P)(CO)PtCl2 react to give R1HgCl and the binuclear chlorine-bridged compounds (R23P)2Pt2Cl2(R1CO)2. No carbonyl insertion is observed when R1Li replaces R12Hg, and Grignard reagents lead to a complex mixture of products. The mechanisms of the mercurial reactions are discussed.

Organic syntheses by means of noble metal compounds. XXXVI. Reactions of carbanions with cyclooctadienepalladium and platinum halide complexes and tetraphenylcyclobutadienepalladium chloride complex

Organic syntheses by means of noble metal compounds. XXXVI. Reactions of carbanions with cyclooctadienepalladium and platinum halide complexes and tetraphenylcyclobutadienepalladium chloride complex

Correction to paper “Long-wave infrared spectra of alkali salts of platinum halide complexes”

Correction to paper “Long-wave infrared spectra of alkali salts of platinum halide complexes”