Arsine Oxide Research Articles

Trimethylarsine oxide and trimethylarsine sulphide complexes with iron(II) and nickel halides

Trimethylarsine sulphide forms tetrahedral iron and nickel complexes of types ML2X2 and [ML4](ClO4)2. Spectroscopic and magnetic data on the arsine oxide compounds ML2X2(M = Fe, Ni; X = Cl, Br, NCS) show them to be bridged octahedral compounds. Cobalt will also produce octahedral isomers of this class in addition to the known tetrahedral derivatives. The large reduction in the ν(As–O) frequencies in the octahedral compounds points to bridging through oxygen rather than through halogen or thiocyanate. Several relatively less stable trimethylphosphine oxide derivatives are reported.

Five-coordination and Paramagnetic Anisotropy

CONSIDERABLE effort has been devoted recently to the establishment of simple experimental criteria by which the stereochemistry of five-coordinate transition metal species can be recognized. They have been primarily concerned with examination of the electronic spectra and, when paramagnetic, the bulk (powder) susceptibilities. These techniques have long been used successfully to differentiate between octahedral and tetrahedral coordination in complexes. It must be emphasized, however, that this success is dependent on only these two alternative stereochemistries having been previously established. A substantial number of five-coordinate complexes of nickel(II) and cobalt(II) have been prepared and some of these have sufficiently distinctive electronic reflectance spectra to reveal their geometry. The point dipole and point charge calculations of Ciampolini1, of Ciampolini and Bettini (personal communication) and of Wood2 have provided bases for their assignment and also for the low temperature polarized single crystal spectra (unpublished work of Kohl, Gerloch and Lewis) of the molecules, M (arsine oxide)4X2 (M = Co, Ni; X = ClO4−, NO3−). By contrast the reflectance spectrum of β-Co(paphy)Cl2 may be equally well assigned3 on the basis of octahedral or tetrahedral stereochemistry although the X-ray data4 established this as five-coordinate.

Tris( n-octyl)arsine oxide (TOCASO) as a reagent for liquid-liquid extraction-II : Extraction of iron(III), zinc(II), cadmium(II), hafnium(IV) and zirconium(IV)

The extraction of the metal ions Fe(III), Zn(II), Cd(II), Hf(IV) and Zr(IV) by tris( n-octyl)arsine oxide (TOCASO), in benzene, has been investigated. The Fe(III), Zn(II) and Cd(II) halides were extracted from the hydrohalic acid solutions while Hf(IV) and Zr(IV) were extracted from citric acid media. The extraction coefficients, E a 0, for zinc and cadmium, were found to increase with increasing pH. E a 0(Zn) reached a limiting of ∼ 1750 in pH range 4·5–6·8 while E a 0(Cd) was found to reach a limiting value of ∼ 63 in pH range 2·7-7·2. Iron(III) was readily extracted at pH values ≧ 0. The extraction coefficient for hafnium(IV) reached a maximum of 200 at pH 2·7 and decreased steeply on either side of this maximum while E a 0[Zr( IV)] reached a maximum value of 140 at pH 4. First power dependence on the reagent concentration was observed for the extraction of Fe(III), Hf(IV), Zr(IV) from aqueous chloride solutions and CdI 2 at low TOCASO concentrations. Second power dependence on the reagent concentration was observed for the extraction of the zinc(II) halides and cadmium(II) iodide at higher TOCASO concentrations, while E a 0(CdBr 2) showed a third power reagent dependence. Infra-red spectra of the products isolated from the equilibration of the metal salts with TOCASO were measured and the arsenic-oxygen, metal-oxygen and metal-halide stretching frequencies have been observed.

Tris( n-octyl)arsine oxide (tocaso) as a reagent for liquid-liquid extraction—1 extraction of mineral acids

Solutions of tris( n-octyl)arsine oxide (TOCASO), ( n-C 8H 17) 3AsO, in benzene have been equilibrated with aqueous solutions of perchloric, hydrochloric, hydrobromic, hydriodic and nitric acids. In the perchloric acid system, the co-extraction of water was noted and the adduct was of the type TOCASO·H 3O +ClO 4 −. Hydrochloric acid formed a 2:1 adduct with TOCASO at aqueous acid concentrations ≧ 1 M. The hydrochloric acid adduct was presumably of the type TOCASOH +HCl 2 −. Hydrobromic and hydriodic acid formed 1:1 adducts at initial aqueous acid concentrations of 0·1 to 2·0M. The co-extraction of 1 mole of water with each mole of acid was observed under these conditions. At acid concentrations ≧4·0M and ≧7·0 M the adducts, TOCASOH +HBr 2 − and TOCASOH +HI 2− were formed without co-extraction of water. Nitric acid formed a 1:1 adduct at initial acid concentrations of 0·1 to 1·0 M with co-extraction of water. As the nitric acid concentration was increased the ratio of acid to reagent increased while the ratio of water to acid decreased concurrently.

Trialkylarsine oxides: Donor properties toward iodine

Equilibrium quotients and extinction coefficients have been measured in carbon tetrachloride solutions, at 25, 35 and 45°, for charge-transfer complexes which form between iodine and tris( n-octyl)arsine oxide, or tris(cyclohexyl)arsine oxide. These molecules, using the equilibrium constants as a criterion, possess a donor strength toward iodine considerably greater than that of triphenylarsine oxide, triphenylarsine or the trialkylphosphine oxides.

The reaction of triphenylphosphine with uranyl salts, and the preparation and infra-red spectra of phosphine and arsine oxide complexes

The reaction of triphenylphosphine with uranyl salts, and the preparation and infra-red spectra of phosphine and arsine oxide complexes

Tertiary Phosphine Oxide and Arsine Oxide Metal Carbonyl Complexes

Tertiary Phosphine Oxide and Arsine Oxide Metal Carbonyl Complexes

Metal Complexes of Diphenylmethylarsine Oxide Involving Co-ordinated Perchlorate Ions

IN recent years, a number of tertiary arsine oxide1 and tertiary phosphine oxide2 complexes of metal salts have been prepared. The metal atom, in all cases, has been shown, using magnetic and spectral data, to display the usual tetrahedral or octahedral stereochemistry. We report here a new class of compound, using diphenylmethylarsine oxide as ligand, in which the metal atom is five co-ordinate with a tetragonal pyramid structure, the fifth position being occupied by a perchlorate group*. Complexes of the composition M(II)(Ph2MeAsO)4(ClO4)2, M = Mn,Fe,Co,Ni,Cu,Zn, are obtained from alcoholic solutions of the arsine oxide and the corresponding perchlorate. X-ray powder photographs indicate that these substances are isostructural. The infra-red spectra of the manganese, cobalt, nickel and zinc complexes in the 1,100 cm−1 region indicate the presence of both coordinated and uncoordinated perchlorate groups, while the spectra of the corresponding iron and copper salts indicate the presence of ionic perchlorate only3.

Some Phosphine Oxide and Arsine Oxide Complexes of Cobalt(II) Nitrate

Some Phosphine Oxide and Arsine Oxide Complexes of Cobalt(II) Nitrate

Reaction of neutron activated arsenic atoms in organic media—II AsPh 3-benzene system

The quantitative distribution of the active products following the neutron irradiation of solutions or arsenic triphenyl and arsenic trichloride in benzene has been investigated. The scavenging action of dissolved oxygen has been explored and the results interpreted in terms of the different kinds of reaction in which the radioactive fragments can participate. Comparative measurements on the behaviour of a solution of diphenyl arsine oxide have also been made. A new method of paper chromatographic separation of the products has been used.

445. Phosphine oxide complexes. Part IV. Tetrahedral, planar, and binuclear complexes of copper(II) with phosphine oxides, and some arsine oxide analogues

445. Phosphine oxide complexes. Part IV. Tetrahedral, planar, and binuclear complexes of copper(II) with phosphine oxides, and some arsine oxide analogues

Comparative Amebacidal Activity of Phenyl Arsine Oxide (Mapharsen), Related Arsenicals and Other Agents 1

SummaryA study of the amebacidal activity in vitro of mapharsen and seven other compounds and three known amebacides is reported. Of the group of agents tested in vitro, mapharsen was most effective and killed E. histolytica in 1 to 20,000 to 1 to 30,000 dilution on 48 hours exposure. 2,4-dihydroxyphenylarsonic acid was effective in 1 to 8,000 dilutions against one strain of E. histolytica and N,N'-disodiumformaldehyde bisulfite-3,3'-diamino-4,4'-di(β-hydroxyethoxy)arsenobenzene in 1 to 3,000 dilution was effective against two other strains. Other drugs had no appreciable effect an amebae in similar concentrations.

Meta-Amino Para-Hydroxy Phenyl Arsine Oxide as an Antisyphilitic Agent

Meta-Amino Para-Hydroxy Phenyl Arsine Oxide as an Antisyphilitic Agent