Catalytic Activation Of Molecular Hydrogen Research Articles

Catalytic activation of molecular hydrogen in alkyne hydrogenation reactions by lanthanide metal vapor reaction products

A rotary metal vapor was used in the synthesis of Lu, Er, Nd, Sm, Yb, and La alkyne, diene, and phosphine complexes. A typical catalytic hydrogenation experiment is described. The lanthanide metal vapor product is dissolved in tetrahydrofuran or toluene and placed in a pressure reaction vessel 3-hexyne (or another substrate) is added, the chamber attached to a high vacuum line, cooled to -196/sup 0/C, evacuated, warmed to ambient temperature and hydrogen is added. The solution is stirred magnetically while the pressure in monitored. The reaction products were analyzed by gas chromatography. Rates and products of various systems are listed. This preliminary survey indicates that catalytic reaction chemistry is available to these metals in a wide range of coordination environments. Attempts to characterize these compounds are hampered by their paramagnetic nature and their tendency to polymerize.

Homogeneous catalytic activation of molecular hydrogen by lanthanoid metal complexes

Co-condensation of lanthanoid metal atoms with internal alkynes generates the first lanthanoid complexes which are capable of homogeneous catalytic activation of molecular hydrogen.

Catalytic Activation of Molecular Hydrogen by Ruthenium Chloride Complexes in N,N-Dimethylacetamide Solution

N, N-Dimethylacetamide solutions of "RuCl3•3H2O", which is a mixture of Ru (IV) and Ru(III), react with hydrogen under mild conditions in stepwise stoichiometric processes to give finally univalent species [Formula: see text]. Reactions 1 and 2 involve heterolytic activation of H2 by a Ru III catalyst and likely proceed via a RuIIIH intermediate; the same catalyst catalyzes the hydrogenolysis of oxygen to water. Reaction 3 involves a RuIIH intermediate. Kinetic parameters are presented for processes 1–3 and the catalytic water production, and are compared with data for some systems that have been studied previously in aqueous acid chloride solutions. Reactions 1 and 2 occur much more readily in the non-aqueous solvent due to a lower activation energy, while reaction 3 occurs only in the non-aqueous system. A detailed interpretation of the data is limited by the uncertain nature of species present in the amide solvent.

Reactions of the pentacyanocobaltate(II) ion: II. Liquid phase hydrogenation and decomposition

In connection with the homogeneous catalytic activation of molecular hydrogen by pentacyanocobaltate(II) ions in aqueous solution, several features of the complex have been investigated. The reaction between hydrogen and pentacyanocobaltate(II) results in an equilibrium, the position of which is independent of the total Co concentration. From the changes of the equilibrium constant with temperature a reaction enthalpy of 11 kcal/mole H 2 has been calculated. The results of kinetic investigations of the hydrogen absorption show that, similarly to the decomposition of [Co(CN) 5] 3- under the influence of water, the rate-determining step is of second order with respect to cobalt. If the hydrogenation is assumed to be a termolecular reaction it shows zero energy of activation. It is, however, also possible to explain the kinetic results by means of other reaction schemes. The most satisfactory is that in which in a rapidly established equilibrium, pentacyanocobaltate(II) first forms a small amount of dimer which subsequently either absorbs hydrogen to form a hydrogenated monomer complex, or decomposes under the influence of water.

Medium Effects in the Homogeneous Catalytic Activation of Molecular Hydrogen by Metal Salts. II. Anion and Solvent Effects for Cupric and Cuprous Salts1

Medium Effects in the Homogeneous Catalytic Activation of Molecular Hydrogen by Metal Salts. II. Anion and Solvent Effects for Cupric and Cuprous Salts¹

Medium Effects in the Homogeneous Catalytic Activation of Molecular Hydrogen by Metal Salts. III. Silver and Mercuric Salts1

Medium Effects in the Homogeneous Catalytic Activation of Molecular Hydrogen by Metal Salts. III. Silver and Mercuric Salts¹

Medium Effects in the Homogeneous Catalytic Activation of Molecular Hydrogen by Metal Salts. I. Cupric and Cuprous Heptanoates in Heptanoic Acid1

Medium Effects in the Homogeneous Catalytic Activation of Molecular Hydrogen by Metal Salts. I. Cupric and Cuprous Heptanoates in Heptanoic Acid¹

Catalytic Activation of Molecular Hydrogen by Cobalt Cyanide Solutions

Catalytic Activation of Molecular Hydrogen by Cobalt Cyanide Solutions

Homogeneous Catalytic Activation of Molecular Hydrogen by Metal Ions and Complexes

Homogeneous Catalytic Activation of Molecular Hydrogen by Metal Ions and Complexes

Homogeneous Catalytic Activation of Molecular Hydrogen in Aqueous Solution by Silver Salts. III Precipitation of Metallic Silver from Solutions of Various Silver Salts

Homogeneous Catalytic Activation of Molecular Hydrogen in Aqueous Solution by Silver Salts. III Precipitation of Metallic Silver from Solutions of Various Silver Salts

Homogeneous Catalytic Activation of Molecular Hydrogen in Aqueous Solution by Silver Salts. II High Temperature Hydrogenation and Exchange Studies

Homogeneous Catalytic Activation of Molecular Hydrogen in Aqueous Solution by Silver Salts. II High Temperature Hydrogenation and Exchange Studies

Catalytic Activation of Molecular Hydrogen by Aluminum Chloride

Catalytic Activation of Molecular Hydrogen by Aluminum Chloride

Homogeneous Catalytic Activation of Molecular Hydrogen in Aqueous Solution by Silver Salts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHomogeneous Catalytic Activation of Molecular Hydrogen in Aqueous Solution by Silver SaltsA. H. Webster and J. HalpernCite this: J. Phys. Chem. 1956, 60, 3, 280–285Publication Date (Print):March 1, 1956Publication History Published online1 May 2002Published inissue 1 March 1956https://doi.org/10.1021/j150537a007RIGHTS & PERMISSIONSArticle Views145Altmetric-Citations28LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (696 KB) Get e-Alerts

Homogeneous Catalytic Activation of Molecular Hydrogen by Cupric Perchlorate

Homogeneous Catalytic Activation of Molecular Hydrogen by Cupric Perchlorate

Mechanism of the Catalytic Activation of Molecular Hydrogen by Metal Ions

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