7783-98-4Relevant academic research and scientific papers
Comparison of Ea values obtained by thermal analysis with energy of 'charge-transfer' spectra for potassium and silver permanganates
Cieslak-Golonka, M.,Ingier-Stocka, E.,Bartecki, A.
, p. 157 - 168 (1995)
The activation energy, Ea taken from the thermal decomposition of KMnO4 and AgMnO4 was compared with the energy of the longest wavelength O→Mn 'charge transfer' (CT) transition. The Ea and CT correlation was fou
The chemical identity of “[Ag(py)2]MnO4” organic solvent soluble oxidizing agent and new synthetic routes for the preparation of [Ag(py)n]XO4 (X = Mn, Cl, and Re, n = 2–4) complexes
Sajó, István E.,Kovács, Gréta B.,Pasinszki, Tibor,Bombicz, Petra A.,May, Zoltán,Szilágyi, Imre M.,Jánosity, Anna,Banerji, Kalyan K.,Kant, Rajni,Kótai, László
, p. 2884 - 2904 (2018)
A widely used oxidizing agent in organic chemistry with an assumed structure of “[Ag(py)2]MnO4” and its perchlorate and perrhenate analogues are studied. Their synthesis in pure form is challenging. In order to clarify the chemical nature of the known compounds and find routes to new derivatives, a systematic study is presented for the synthesis of [Ag(py)n]XO4 (X = Mn, Cl, and Re, n = 2–4) complexes. Ten complexes including four new derivatives, [Ag(py)4]MnO4, [Ag(py)4]MnO4·4[Ag(py)2]MnO4, [Ag(py)2]ClO4·0.5 py, and [Ag(py)2]ReO4, are synthesized and characterized. The chemical identity of “Ag(py)2MnO4” is also clarified. A novel route to prepare [Ag(py)2]MnO4 is developed. The reaction of AgXO4 salts with neat pyridine followed by various crystallization techniques is used to prepare [Ag(py)2]XO4, [Ag(py)4]XO4, [Ag(py)4]XO4·4[Ag(py)2]XO4, and [Ag(py)2]XO4·0.5py (X = Cl, Mn) complexes. The solid phase structure of [Ag(py)2]MnO4·0.5py is determined (a = 19.410 ?, b = 7.788 ?, c = 21.177 ?, β = 104.20°, C2/c (15), Z = 4 (3a)). [Ag(py)2]+ cations in the crystal form dimeric units where silver ions are connected by oxygen atoms of two MnO4– anions. The Ag…Ag distance is indicative of argentophilic interactions. The pyridine ring π…π interactions contribute to the stability of the crystal lattice.
MAGNETIC PROPERTIES OF SILVER PERMANGANATE.
Sperka,Fritzer
, p. 1275 - 1277 (1988)
Magnetic susceptibility measurements at various temperatures and magnetic flux densities and diffuse reflectance spectra of carefully prepared and handled silver permanganate (AgMnO//4) are reported. The key value for X//M(AgMnO//4) is (2. 75 plus or minus 0. 1) multiplied by 10** minus **1**0 m**3 mol** minus **1 at 300K and 1. 3T. The results confirm the model of a multicentre interaction suggested in the literature. In addition, the results clearly point at the importance of the preparation and storage of the sample under well-defined and reproducible conditions since the magnetic properties change significantly with higher temperatures tending to an increased paramagnetic behaviour.
An unknown component of a selective and mild oxidant: Structure and oxidative ability of a double salt-type complex having κ1O-coordinated permanganate anions and three- and four-fold coordinated silver cations
Kovács, Gréta Bettina,May, Nóra V.,Bombicz, Petra Alexandra,Klébert, Szilvia,Németh, Péter,Menyhárd, Alfréd,Novodárszki, Gyula,Petrusevski, Vladimir,Franguelli, Fernanda Paiva,Magyari, József,Béres, Kende,Szilágyi, Imre Miklós,Kótai, László
, p. 28387 - 28398 (2019/09/30)
Compounds containing redox active permanganate anions and complexed silver cations with reducing pyridine ligands are used not only as selective and mild oxidants in organic chemistry but as precursors for nanocatalyst synthesis in low-temperature solid-phase quasi-intramolecular redox reactions. Here we show a novel compound (4Agpy2MnO4·Agpy4MnO4) that has unique structural features including (1) four coordinated and one non-coordinated permanganate anion, (2) κ1O-permanganate coordinated Ag, (3) chain-like [Ag(py)2]+ units, (4) non-coordinated ionic permanganate ions and an [Ag(py)4]+ tetrahedra as well as (5) unsymmetrical hydrogen bonds between pyridine α-CHs and a permanganate oxygen. As a result of the oxidizing permanganate anion and reducing pyridine ligand, a highly exothermic reaction occurs at 85 °C. If the decomposition heat is absorbed by alumina or oxidation-resistant organic solvents (the solvent absorbs the heat to evaporate), the decomposition reaction proceeds smoothly and safely. During heating of the solid material, pyridine is partly oxidized into carbon dioxide and water; the solid phase decomposition end product contains mainly metallic Ag, Mn3O4 and some encapsulated carbon dioxide. Surprisingly, the enigmatic carbon-dioxide is an intercalated gas instead of the expected chemisorbed carbonate form. The title compound is proved to be a mild and efficient oxidant toward benzyl alcohols with an almost quantitative yield of benzaldehydes.
Reversible anion exchange and catalytic properties of two cationic metal-organic frameworks based on Cu(I) and Ag(I)
Fei, Honghan,Rogow, David L.,Oliver, Scott R. J.
, p. 7202 - 7209 (2010/07/08)
We report the synthesis and characterization of two Ag(I)/Cu(I)-based cationic metal-organic frameworks and their application in both heterogeneous catalysis and anion exchange. The Cu(I)-based material was designed from our previously reported Ag(I) cationic topology. Both structures consist of cationic layers with π-π stacked chains of alternating metal and 4,4′-bipyridine. α,Ω-Alkanedisulfonate serves as an anionic template, electrostatically bonding to the cationic layers. Due to weak interaction between the sulfonate template and cationic extended framework, both materials display reversible anion exchange for a variety of inorganic species. Indeed, the Ag(I)-based material exhibits highly efficient uptake of permanganate and perrhenate anion trapping, a model for pertechnetate trapping. The materials also display heterogeneous Lewis acidity, likely due to the coordinatively unsaturated metal sites which only bind to two bipy nitrogens and a weak interaction with one sulfonate oxygen. A comparative study on the influence of structure versus size selectivity and reusability for both exchange and catalysis is discussed.
