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Showing papers on "Iodide published in 1984"


Journal ArticleDOI
TL;DR: In this article, the reaction of 4-bromopyridine with 2-methyl-3-butyn-2-ol in diethylamine in the presence of bis(triphenylphosphine)palladium(II) chloride and copper(I) iodide was described.

107 citations


Journal ArticleDOI
TL;DR: It is postulated that lactoperoxidase generates hypoiodous acid and that the latter is the active intermediate in the various reactions involving iodide.

88 citations


Journal ArticleDOI
TL;DR: In this paper, the rate constants for reaction of hydroxyl radicals with ferrocyanide, thiocyanate, iodide, and formate ions and with 2-propanol and tert-butanol have been measured over the 19 −79°C temperature range.

85 citations


Journal ArticleDOI
TL;DR: There was a significant correlation between the iodide level in the breast milk and dietary iodine as estimated by a food frequency questionnaire, and iodized salt intake was significantly related to the iodine content of the breast Milk.
Abstract: In addition to iodized salt, the American diet is inadvertently supplemented with iodine from other foods, such as bread and cow's milk. The iodine content of breast milk has not been assessed recently in this country. Sixty-one samples of breast milk from 37 women were analyzed for iodide content using an iodide-selective electrode method. Mean breast milk iodide level on initial samples for this population was 178 micrograms/L (range 29 to 490 micrograms/L), about four times the recommended daily allowance for infants. Iodide levels in breast milk did not correlate with the age of the infant (ie, stage of lactation). There was a significant correlation between the iodide level in the breast milk and dietary iodine as estimated by a food frequency questionnaire, and iodized salt intake was significantly related to the iodide content of the breast milk.

81 citations


Journal ArticleDOI
TL;DR: Non-stoichiometric (excessive) consumption of hydrogen peroxide (H2O2), which was observed in various lactoperoxidase-catalysed reactions, was tested and suggests a pseudo-catalytic side reaction which can competitively interfere with the I2/I-3 generation or the iodination reaction.
Abstract: Non-stoichiometric (excessive) consumption of hydrogen peroxide (H2O2), which was observed in various lactoperoxidase-catalysed reactions, was tested in the lactoperoxidase/H2O2/iodide system. In preliminary experiments the suitability of the system was tested with special regard to the triiodide (I−3) absorption and the I2/I−3 equilibrium. Triiodide equilibrium concentrations evaluated theoretically and experimentally were compared after adding a known amount of iodine (I2) to solutions containing variable I− concentrations. A close fit of the two methods was only obtained if experiments were carried out in pure aqueous or 0.001 M H2SO4 medium. The presence of various anions, e.g. OH− and Cl−, led to a measurable decrease in I−3 and I2 equilibrium concentrations. These ions are able to displace competitively I− in forming association products with I+ and I2. When I+ and I2 were generated enzymatically by lactoperoxidase and hydrogen peroxide, additional interactions with H2O2 were observed. Depending on the enzyme and iodide concentrations, variable amounts of H2O2 disappeared non-productively. Due to its ambivalent redox reactivity, part of the H2O2 is not reduced to H2O in the enzyme-catalysed generation of iodine, but undergoes oxidation to O2 by an oxidized iodine compound. This suggests a pseudocatalatic side reaction which can competitively interfere with the I2 I−3 generation or (and) the iodination reaction.

70 citations


Journal ArticleDOI
TL;DR: In this paper, the authors describe ion exchange reactions of In2Mo6X6 with alkali iodide and chloride salts at 550°C to give mixed solid solutions In2−xMxMo 6X6 (M=Li, Na, K, Rb, Cs; X=Se, Te).

68 citations


Journal ArticleDOI
TL;DR: Various (β-lactams are prepared from the corresponding β-amino acids under mild reaction conditions in high yields by employing 2-chloro-1-methylpyridinium iodide as a condensing reagent.
Abstract: Various (β-lactams are prepared from the corresponding β-amino acids under mild reaction conditions in high yields by employing 2-chloro-1-methylpyridinium iodide as a condensing reagent.

68 citations


Journal ArticleDOI
TL;DR: In this article, the ternary system CuI-Cu 2 O-P 2 O 5, from which Cu 2+ ion formation has been excluded, is described and compared with that in the corresponding Ag + -based system.

60 citations


Journal ArticleDOI
TL;DR: A new fungicidal system composed of ferrous ion, H2O2, and iodide is described and compared with the myeloperoxidase-hydrogen peroxide-halide system, which had similar activity against Aspergillus fumigatus spores and the Candida albicans yeast phase.
Abstract: A new fungicidal system composed of ferrous ion, H2O2, and iodide is described and compared with the myeloperoxidase-hydrogen peroxide-halide system. Both systems had similar activity against Aspergillus fumigatus spores and the Candida albicans yeast phase, but only the ferrous ion-hydrogen peroxide-iodide system was inhibited by hydroxyl radical scavengers.

58 citations


Journal ArticleDOI
TL;DR: The zwitterionic donor-pi-acceptor adduct Z-β-(N-methyl-2-pyridyl)-α-cyano-4-styryl dicyanomethids (trivial name: picolyl-tricyanoquinodimethan, P3CNQ) as discussed by the authors was constructed using CAD-4F diffractometer Mo Ka data refined to R = 5.1 per cent.
Abstract: The reaction of the lithium salt of 7,7,8,8-tetracyanoquinodimethan (TCNQ) with 1.2-dimethylpyridinium iodide in ethanol leads to a conventional charge-transfer salt. However, the same reagents dissolved in acetonitrile yield crystals which belong to space group P21/c, with unit cell constants a = 1493.5(2), b = 720.9(2) (stack axis), C = 1380.2(3) pm, β = 107.06(2)°. Z = 4 for Cl8H13N4. 1746 unique CAD-4F diffractometer Mo Ka data refined to R = 5.1 per cent, to yield the structure of the zwitterionic donor-pi-acceptor adduct Z-β-(N-methyl-2-pyridyl)-α-cyano-4-styryl dicyanomethids (trivial name: picolyl-tricyanoquinodimethan, P3CNQ). The pyridinium ring is inclined 30.13° from the quinodimethan 6-membered ring. The salt is diamagnetic, and the pyridinium N atom stacks above the dicyanomethide portion of the next molecule along the b axis.

58 citations


Journal ArticleDOI
TL;DR: In this paper, the authors show evidence of formation of complexes cationiques Ag 4 I 3+ dans les solutions d'iodure d'argent d'ioniure.
Abstract: L'etude par diffraction RX sur des solutions aqueuses de nitrate et de perchlorate d'argent indique une coordination 4 autour de l'atome Ag avec une longueur de liaison Ag-O de 2,4 A. Dans les solutions de nitrate, les anions sont monocoordines a Ag tandis que dans les solutions de perchlorate, les anions n'entrent pas dans la premiere sphere de coordination. Mise en evidence de formation de complexes cationiques Ag 4 I 3+ dans les solutions d'iodure

Journal ArticleDOI
TL;DR: The reaction mechanism of the potassium ion transfer from aqueous to nitrobenzene phases, facilitated by valinomycin present in the organic phase, was elucidated by polarography at the ascending water electrode and chronopotentiometry at the stationary water electrode as discussed by the authors.

Journal ArticleDOI
TL;DR: In this article, the nuclear cobalt ion in heptamethyl cobyrinate iodide, Cob(II)ester·I, was found to assume a distorted square-planar geometry of Co-N4 type with iodide as a counterion in a polar solvent (methanol) and a square-pyramidal one with the iodide ion coordinated at one of the axial positions in apolar solvents such as dichloromethane, benzene, and toluene.
Abstract: The nuclear cobalt(II) ion in heptamethyl cobyrinate iodide, Cob(II)ester·I, was found to assume a distorted square-planar geometry of Co–N4 type with iodide as a counterion in a polar solvent (methanol) and a square-pyramidal one of Co–N4I type with the iodide ion coordinated at one of the axial positions in apolar solvents such as dichloromethane, benzene, and toluene. The redox chemistry of Cob(II)ester·I and heptamethyl cobyrinate perchlorate, [Cob(II)ester]ClO4, was investigated in various organic solvents by means of cyclic voltammetry and controlled-potential electrolysis. The Co(II)/Co(I) and Co(III)/Co(II) redox potentials for [Cob(II)ester]ClO4 exhibited cathodic shifts as either solvent basicity or polarity was raised, and were found to be in the anodic side relative to the corresponding potentials for CoII(tpp) under identical conditions. The medium effect on the redox behavior of hydrophobic vitamin B12 was discussed in connection with the microenvironmental effect on vitamin B12 placed in th...

Journal ArticleDOI
TL;DR: Palladium and iodide catalyse the oxidative carbonylation of amines by CO, O2, and alcohols to give carbamates in high yields.
Abstract: Palladium and iodide catalyse the oxidative carbonylation of amines by CO, O2, and alcohols to give carbamates in high yields.

Journal ArticleDOI
TL;DR: In this article, a postcolumn fluorescence detection system was introduced for the detection of oxidizable anions in anion-exchange chromatography, and the anions (nitrite, thiosulfate, and iodide) were analyzed by this system using their reaction with Ce(IV) to produce the fluorescent species Ce(III).
Abstract: A postcolumn fluorescence detection system is introduced for the detection of oxidizable anions in anion-exchange chromatography. The anions (nitrite, thiosulfate, and iodide) are analyzed by this system using their reaction with Ce(IV) to produce the fluorescent species Ce(III) in a postcolumn-packed bed reactor. In addition, the nitrate and nitrite anions are determined simultaneously by using a postcolumn copperized reductor to reduce nitrate to nitrite prior to its oxidation with Ce(IV). The detection limit of this method is at the low ppb level with a linear dynamic range covering 2-3 orders of magnitude.

Journal ArticleDOI
TL;DR: In this paper, Menezes et al. showed that adding Cu ions to the iodide solution significantly decreases photoanode decomposition, at up to 11.7% conversion efficiency under 120mW/cm2 tungsten-halogen illumination.
Abstract: Surface optimization of n‐CuInSe2 crystals by chemical etching in Br2/MeOH and subsequent thermal oxidation results in >10% efficient photanodes in neutral aqueous polyiodide. The etchant removes a near‐stoichiometric surface layer and thermal oxidation leads to In–O bond formation. We find from (photo) electrochemical studies in acetonitrile and in the iodide electrolyte that, upon semiconductor decomposition, Cu ions are released into the solution, consistent with solid state chemical studies that show the existence of the chalcopyrite phase also towards Cu‐poor compositions. Addition of Cu ions, as also reported by S. Menezes, H. J. Lewerenz, and K. J. Bachmann [Nature (London) 305, 615 (1983)] or Cu and In ions to the iodide solution drastically decreases photoanode decomposition. Covering the electrode with an extra film of oxidized indium results in true stabilization, at up to 11.7% conversion efficiency under 120‐mW/cm2 tungsten‐halogen illumination. Because, in the presence of Cu ions and under i...

Patent
10 Apr 1984
TL;DR: In this paper, a process for the hydrometallurgical recovery of gold from materials containing gold comprising leaching the materials with a lixiviant containing iodine is described.
Abstract: A process for the hydrometallurgical recovery of gold from materials containing gold comprising leaching the materials with a lixiviant containing iodine. To a solution concentrated with natural salts is added elemental iodine until saturated, whereupon mineral sulfides in the ore zone charged with this solution react with the iodine to form iodide. Additional elemental iodine is then added to this iodide-bearing solution until the desired concentration of total iodine and ratio of iodine to iodide are achieved for optimum leaching. The lixiviant is then circulated through the ore zone until all the gold is dissolved. Gold is subsequently recovered on activated charcoal. The excess iodide formed during the process is reoxidized to iodine electrochemically in a special diaphragm cell to regenerate the lixiviant.

Journal ArticleDOI
TL;DR: The X-ray crystal and molecular structure of [I−L4+]3+ 3I−3MeCN·H2O, L = N4Me4(C6H12)6, shows on iodide anion to be encapsulated symmetrically into the spherical intramolecular cavity of the macrotricycle L4+ and held in place by the ectrostatic potential of the four quaternary ammonium sites arranged at the corners of an almost perfect tetrahedron; the N+⋯ I− distances average to 4
Abstract: The X-ray Crystal and molecular structure of [I–L4+]3+ 3I–˙3MeCN·H2O, L = N4Me4(C6H12)6, shows on iodide anion to be encapsulated symmetrically into the spherical intramolecular cavity of the macrotricycle L4+ and held in place by the ectrostatic potential of the four quaternary ammonium sites arranged at the corners of an almost perfect tetrahedron; the N+⋯ I– distances average to 4.54(2)A whereas the distances between iodide and the carbon atoms of the [CH2]6 chains are of van der Waals type or longer.

Journal ArticleDOI
TL;DR: Etude de la dissociation en phase gazeuse d'une serie d'ions agregats d'halogenures alcalins de masse elevee produits par bombardement sur des solides as mentioned in this paper.
Abstract: Etude de la dissociation en phase gazeuse d'une serie d'ions agregats d'halogenures alcalins de masse elevee produits par bombardement sur des solides

Journal ArticleDOI
01 Oct 1984
TL;DR: In this article, the temperature dependences of spin-lattice relaxation times and 1H NMR second moments were observed for guanidinium chloride, bromide, iodide, thiocyanate, nitrate, and perchlorate.
Abstract: The temperature dependences of 1H NMR spin-lattice relaxation times and 1H NMR second moments were observed for guanidinium chloride, bromide, iodide, thiocyanate, nitrate, and perchlorate. The results of the NMR experiments carried out with the crystals of these compounds except the last one can be interpreted in terms of the C3 reorientation of the cation about its symmetry axis. The solid-solid phase transition at 454 K reported for guanidinium perchlorate could be resolved into two phase transitions taking place successively at 450 and 452 K. In the low temperature phase of this salt, the C3 reorientation of the cation is activated. The occurrence of cationic self-diffusion in the high temperature phase was confirmed by the measurements of 1H NMR relaxation times. The NMR motional parameters are evaluated for these cationic motions in the present salts. The phase transition temperature of guanidinium iodide was strongly depended on the grain size of the sample employed. Guanidinium bromide yielded a single 81Br NQR line at room temperature indicating that all bromide ions in the crystal are crystallographically equivalent in agreement with the results of X-ray analysis.

Journal ArticleDOI
TL;DR: Over a period of days, the selenonium intermediate undergoes spontaneous elimination to form alanine and dimethyl selenide, which reacts with methyl iodide to give the trimethylselenonium product in over 90% yield.

Journal ArticleDOI
TL;DR: In this paper, a system was described which uses a selective electrode for potentiometric detection of anions in natural waters after ion exchange separation, where a linear relationship exists between iodide concentration and potential in the sub-Nernstian range (0 −100 μM).

Journal ArticleDOI
TL;DR: In this article, the authors found an absence of binding on thyroxine-binding globulin, but thyroid and triiodothyronine were bound to albumin with a maximal capacity 50 times higher than in human serum.
Abstract: Summary: Mature human milk samples from young healthy women on an equilibrated diet contained a mean of 81 ng/ml total iodine. Iodide represented a mean of 77% of the total iodine. Of the 22 ng/ml organic iodine, there was about 1 ng thyroxine and triiodothyronine and, after pepsin hydrolysis, up to 40% of organic iodine in monoiodotyrosine form. By electrophoresis, after incubation with radioactive thyroid hormone, we found an absence of binding on thyroxine-binding globulin, but thyroxine and triiodothyronine were bound to albumin with a maximal capacity 50 times higher than in human serum. All these differences did not favor transport of iodinated compounds from maternal serum to milk. In conclusion, milk iodide was taken up by newborn thyroid to make thyroid hormones.

Journal ArticleDOI
TL;DR: In this article, the complexation properties of new azobenzo-crown ethers with alkali and alkaline earth metal iodide salts were investigated in acetonitrile solution spectrophotometrically.
Abstract: New crown ethers which have a benzeneazo group as a building block of a macrocyclic polyether ring. The complexation properties of these new azobenzo-crown ethers with alkali and alkaline earth metal iodide salts were investigated in acetonitrile solution spectrophotometrically. The complex formation constants were evaluated for alkali metal salts. The azo group is not particularly a favorable component of a crown ether macrocycle for stabilizing the metal complexes.

Journal ArticleDOI
TL;DR: In this paper, a model of packing of MV2+ in the MPS3 host lattices has been established which accounts for the different intercalation rates, and the reduced product, MV˙+, has been studied in both the chloride, iodide and palladate compounds.
Abstract: Infrared and Raman spectra (1800–200 cm–1) of methyl viologen (1,1′-dimethyl-4,4′-bipyridyl dication or MV2+)([1H8] and [2H8] derivatives) have been recorded for the chloride, iodide and palladate salts and for the intercalated compounds of formula M0.84 PS3–(MV)0.16(with M = Mn and Cd), FePS3–(MV)0.15 and Zn0.71 PS3–(MV)0.29. Complete assignments have been proposed for all these species. The methyl viologen appears to be intercalated in its dicationic form and is weakly interacting with the host lattice. In the ZnPS3 system the MV2+ pyridyl rings are twisted while in MnPS3, CdPS3, and FePS3 the cation rings are coplanar and parallel to the sulphur layers. From these results, a model of packing of MV2+ in the MPS3 host lattices has been established which accounts for the different intercalation rates. Finally, the reduced product, MV˙+, has been studied in both the chloride salt and the CdPS3 intercalation compound; in the latter case the radical cation behaves as though diluted and trapped inside an inert matrix, demonstrating unexpected stability.

Journal ArticleDOI
TL;DR: Trimethylsilyl chloride-sodium iodide has been used for the mild removal of methoxyethoxymethyl ethers as discussed by the authors, and it has been shown that it can be used for removal of methyl ethers.

Journal ArticleDOI
01 Jan 1984-Analyst
TL;DR: In this article, the authors used micellar hexadecyltrimethylammonium chloride as the mobile phase for the separation of iodate, nitrite, bromide, nitrate and iodide.
Abstract: High-performance liquid chromatography using micellar hexadecyltrimethylammonium chloride as the mobile phase is shown to provide a versatile and efficient technique for the separation of iodate, nitrite, bromide, nitrate and iodide. The mechanism of distribution of the inorganic anions using an aqueous micellar mobile phase with a hydrophobic column packing is investigated. Anion partitioning between the micelles and the mobile phase and between the conditioned stationary phase and the mobile phase both contribute to the retention of the inorganic anions. The influence of the concentrations of hexadecyltrimethylammonium chloride, sodium chloride and acetonitrile on the retention mechanism is also investigated.The application of micellar chromatography to the analysis of anions is demonstrated via the determination of nitrate and nitrite in domestic water samples.

Journal ArticleDOI
TL;DR: Cristallisation dans le systeme triclinique et affinement de la structure jusqu'a R=0,054 as mentioned in this paper, en couches paralleles au plan ab des cations complexes and des molecules de nitrobenzene
Abstract: Cristallisation dans le systeme triclinique et affinement de la structure jusqu'a R=0,054. Empilement en couches paralleles au plan ab des cations complexes et des molecules de nitrobenzene

Journal ArticleDOI
TL;DR: In this paper, a unified I-Pd-I-PD-PD lineaire and deux coordinats isocyanure terminaux sur chaque Pd are presented.
Abstract: (CH 3 NC) 4 Pd 2 I 2 cristallise dans P1 avec Z=2; affinement jusqu'a R=0,039 (etude a 140 K). Structure non pontee avec une unite I-Pd-Pd-I lineaire et deux coordinats isocyanure terminaux sur chaque Pd

Journal ArticleDOI
TL;DR: In this article, it was established by single-crystal X-ray diffraction methods at 295 K that this is a µµ'-diiodobridged dimer, with four-coordinate copper(I), [(py)2CuI2Cu(py) 2]
Abstract: Copper(I) iodide on recrystallization from neat pyridine yields a 1 : 2 adduct; it is established by single-crystal X-ray diffraction methods at 295 K that this is a µµ'-diiodobridged dimer, with four- coordinate copper(I), [(py)2CuI2Cu(py)2]. Crystals are orthorhombic, C2221, a 14.578(4), b 10.448(3), c 31.559(7) A, Z = 8 dimers. Cu. . .Cu is 2.699(5) A.