Reaction of hydroxide ion with manganese(III) tetramesitylporphyrin and the oxidation states of manganese tetramesitylporphyrins

1990 ◽  
Vol 29 (7) ◽  
pp. 1422-1427 ◽  
Author(s):  
Ramesh D. Arasasingham ◽  
Thomas C. Bruice
Keyword(s):  
Oxidation States ◽  
Hydroxide Ion

OXIDATION STATES OF MANGANESE IN FUSED ALKALI NITRATES

1963 ◽  
Vol 41 (1) ◽  
pp. 108-111 ◽  
Author(s):  
Ruth M. Bennett ◽  
Owen G. Holmes
Keyword(s):  
Aqueous Solution ◽  
Oxidation States ◽  
Great Similarity ◽  
Hydroxide Ion ◽  
Alkaline Aqueous Solution

When dissolved in fused alkali nitrate, manganese (II) is oxidized to MnO2. In the same solvent MnO4− decomposes to MnO2. Peroxide ion arrests the decomposition at MnO42−, while the presence of hydroxide ion results in the formation of MnO43−. The spectra of MnO42− and MnO43− in molten nitrate show great similarity to their spectra in alkaline aqueous solution.

MicroEXAFS study into the oxidation states of copper coloured Hispano-Moresque lustre decorations

2003 ◽  
Vol 104 ◽  
pp. 519-522 ◽  
Author(s):  
A. D. Smith ◽  
T. Pradell ◽  
J. Molera ◽  
M. Vendrell ◽  
M. A. Marcus ◽  
...  
Keyword(s):  
Oxidation States

Acceptorless amine dehydrogenation and transamination using Pd-doped layered double hydroxides

2018 ◽  
Author(s):  
Diana Ainembabazi ◽  
Nan An ◽  
Jinesh Manayil ◽  
Kare Wilson ◽  
Adam Lee ◽  
...  
Keyword(s):  
Layered Double Hydroxides ◽  
Oxidation States ◽  
Secondary Amines ◽  
Primary Amines ◽  
Acid Dissolution ◽  
Oxidative Amination ◽  
Strong Function ◽  
Excellent Activity ◽  
High Yields ◽  
Double Hydroxides

<div> <p>The synthesis, characterization, and activity of Pd-doped layered double hydroxides (Pd-LDHs) for for acceptorless amine dehydrogenation is reported. These multifunctional catalysts comprise Brønsted basic and Lewis acidic surface sites that stabilize Pd species in 0, 2+, and 4+ oxidation states. Pd speciation and corresponding cataytic performance is a strong function of metal loading. Excellent activity is observed for the oxidative transamination of primary amines and acceptorless dehydrogenation of secondary amines to secondary imines using a low Pd loading (0.5 mol%), without the need for oxidants. N-heterocycles, such as indoline, 1,2,3,4-tetrahydroquinoline, and piperidine, are dehydrogenated to the corresponding aromatics with high yields. The relative yields of secondary imines are proportional to the calculated free energy of reaction, while yields for oxidative amination correlate with the electrophilicity of primary imine intermediates. Reversible amine dehydrogenation and imine hydrogenation determine the relative imine:amine selectivity. Poisoning tests evidence that Pd-LDHs operate heterogeneously, with negligible metal leaching; catalysts can be regenerated by acid dissolution and re-precipitation.</p> </div> <br>

Catalytic Fluorination of Boron Compounds at a Bismuth Redox Platform

2019 ◽  
Author(s):  
Oriol Planas ◽  
Feng Wang ◽  
Markus Leutzsch ◽  
Josep Cornella
Keyword(s):  
Transition Metal ◽  
Main Group ◽  
Group Element ◽  
Oxidation States ◽  
Boron Compounds ◽  
Main Text ◽  
Main Group Element ◽  
Rational Ligand Design ◽  
Supplementary Material

The ability of bismuth to maneuver between different oxidation states in a catalytic redox cycle, mimicking the canonical organometallic steps associated to a transition metal, is an elusive and unprecedented approach in the field of homogeneous catalysis. Herein we present a catalytic protocol based on bismuth, a benign and sustainable main-group element, capable of performing every organometallic step in the context of oxidative fluorination of boron compounds; a territory reserved to transition metals. A rational ligand design featuring hypervalent coordination together with a mechanistic understanding of the fundamental steps, permitted a catalytic fluorination protocol based on a Bi(III)/Bi(V) redox couple, which represents a unique example where a main-group element is capable of outperforming its transition metal counterparts.<br>A main text and supplementary material have been attached as pdf files containing all the methodology, techniques and characterization of the compounds reported.<br>

Residual phase lignin in haft cooking related to the conditions in the cook

1997 ◽  
Vol 12 (4) ◽  
pp. 225-229
Author(s):  
Cart-in A-S. Gustavsson ◽  
Chritofer T. Lindgren ◽  
Mikael E. Lindström
Keyword(s):  
Hydrogen Sulfide ◽  
Ionic Strength ◽  
Sodium Ion ◽  
Ion Concentration ◽  
Constant Composition ◽  
Hydroxide Ion ◽  
Sulfide Ion ◽  
Residual Phase ◽  
Kraft Cooking ◽  
Very High

Abstract The amount of lignin reacting according to the slow residual phase, i.e. the residual phase lignin, is in many perspectives an interesting issue. The purpose of the present investigation was to develop a mathematical model to show how the amount of residual phase lignin in the kraft cooking of spruce chips (Picm ahies) depends on the conditions in the earlier phases of the cook. The variables studied were hydroxide ion concentration, hydrogen sulfide ion concentration and ionic strength. The liquor-to-wood ratio during pulping was very high to maintain approximately constant chemical concentrations throughout each experiment (so called "constant composition" cooks). An increase in hydroxide ion concentration andtor hydrogen sulfide ion concentration leads to a decrease in the amount of residual phase lignin, while an increase in ionic strength, i.e. sodium ion concentration, leads to an increase. A signiticant result is that the hydrogen sulfide ion concentration has a pronounced influence on the amount of residual phase lignin during a cook at a low hydroxide ion concentration. The amount of residual phase lignin expressed as % lignin on wood, L,, can be described by the following equation developed for "constant composition" cooks (when cooking with a constant sodium ion concentration of 2 mol/L): LT=0,55-0.32*[HO-](-1,3)*ln[HS-] This equation is valid for a concentration of HO- in the range from 0.17 to 1.4, and a hydrogen sulfide ion concentration from 0.07 to 0.6 mol/L.

THE OXIDATION STATES OF IRON AND VOLATILE COMPOSITIONS OF EXPEDITION 352 GLASSES

2019 ◽  
Author(s):  
M. Brounce ◽  
◽  
Mark K. Reagan ◽  
Daniel A. Coulthard ◽  
Katherine A. Kelley ◽  
...  
Keyword(s):  
Oxidation States

Kinetic salt effects in the hydrolysis of ethyl malonate, methyl glutarate and ethyl adipate semiesters

1986 ◽  
Vol 51 (12) ◽  
pp. 2781-2785 ◽  
Author(s):  
M. Martín Herrera ◽  
J. J. Maraver Puig ◽  
F. Sánchez Burgos
Keyword(s):  
Salt Effect ◽  
Alkaline Media ◽  
Salt Effects ◽  
Coulombic Interaction ◽  
Hydroxide Ion ◽  
Ethyl Malonate ◽  
Hydrolysis Of

A study is made on the kinetic salt effect on the reaction of hydrolysis of several charged esters in alkaline media. The results are interpreted on the basis of the coulombic interaction, the salting in of hydroxide ion and a third component depending on size of the substrate.

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