Author: Michael John Saliby
Publisher:
ISBN:
Category : Ligands
Languages : en
Pages : 482
Book Description
Investigations in the Chemistry of Some Chromium (III), Cobalt (III), and Rhodium (III) Complexes Containing the Ligand Beta, Beta Prime, Beta Double Prime-triaminotriethylamine
Author: Michael John Saliby
Publisher:
ISBN:
Category : Ligands
Languages : en
Pages : 482
Book Description
Publisher:
ISBN:
Category : Ligands
Languages : en
Pages : 482
Book Description
Studies on Bridged Complexes of Cobalt (III) and Chromium (III).
Author: Abbas Abbas Mohammad El-Said El-Awady
Publisher:
ISBN:
Category : Chromium
Languages : en
Pages : 356
Book Description
Publisher:
ISBN:
Category : Chromium
Languages : en
Pages : 356
Book Description
The Polarographic and Spectroscopic Studies of Cis and Trans Coordination Compounds of Chromium (III), Rhodium (III), and Cobalt (III)
Author: Ting-Tung Lea
Publisher:
ISBN:
Category :
Languages : en
Pages : 96
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 96
Book Description
The Stereochemistry of Some Cobalt (III) Complexes Containing Optically Active Ligands
Author: Bennie Anthony Ferrone
Publisher:
ISBN:
Category : Cobalt organic compounds
Languages : en
Pages : 186
Book Description
Publisher:
ISBN:
Category : Cobalt organic compounds
Languages : en
Pages : 186
Book Description
Facilitating Multi-electron Reactivity at Low-coordinate Cobalt Complexes Using Redox-active Ligands
Author: Aubrey L. Smith
Publisher:
ISBN:
Category : Charge exchange
Languages : en
Pages :
Book Description
In this study, we describe a detailed investigation of cobalt complexes containing redox-active ligands. We have prepared an electronic series of the complex in three oxidation states: [CoIII(ap)2]-, CoIII(isq)(ap), and [CoIII(CH3CN)(isq)2]+. Characterization shows that the metal center remains cobalt(III) through the redox changes and indicates that the oxidation state changes occur with gain or loss of electrons from the ligand set. While CoIII(isq)(ap) reacts with halide radicals to form a new cobalt-halide bond in a single electron reaction, [CoIII(ap)2]- appears to be prone to multi-electron reactivity in reactions with sources of "Cl+". Both reactions occur with electrons derived from the ligand set. Mechanistic studies suggest a single, two electron step is responsible for the bond-formation. Similarly, [CoIII(ap)2]- reacts with alkyl halides to pseudo-oxidatively add the alkyl at the cobalt center. The product of the reaction can be isolated and fully characterized and was found to be best assigned as CoIII(alkyl)(isq)2. This assignment indicates that the reaction occurs, again, with the new bond formed with two electrons formally derived from the ligand set and with no change in oxidation state at the metal center. Mechanistic investigations of the pseudo-oxidative addition suggest the reaction is SN2-like. The reaction occurs with a wide scope of alkyl halides, including those containing beta-hydrogens. : The cross-coupling reaction of CoIII(alkyl)(isq)2 with RZnX forms a new carbon-carbon bond. Similarly, the two electron oxidized complex [CoIII(CH3CN)(isq)2]+ reacts with organozinc reagents to couple two carbon nucleophiles and form a new carbon-carbon bond. Both reactions are successful with both sp2 and sp3 carbons. When followed substoichiometrically, the homocoupling reaction can be observed to form CoIII(alkyl)(isq)2. This indicates that the homocoupling and cross-coupling reactions proceed by the same mechanism. However, both reactions have low yields. The yield of the reactions are decreased by steric bulk of the alkyl or aryl fragments or around the metal center created by substituents on the ligand. Also, while the steric congestion disfavors the addition of the first alkyl fragment, the addition of the second alkyl fragment and subsequent rapid elimination of the coupling product is almost completely inhibited. This result also implies that the coupling of the two alkyl fragments is entirely inner-sphere requiring installation of both for coupling.
Publisher:
ISBN:
Category : Charge exchange
Languages : en
Pages :
Book Description
In this study, we describe a detailed investigation of cobalt complexes containing redox-active ligands. We have prepared an electronic series of the complex in three oxidation states: [CoIII(ap)2]-, CoIII(isq)(ap), and [CoIII(CH3CN)(isq)2]+. Characterization shows that the metal center remains cobalt(III) through the redox changes and indicates that the oxidation state changes occur with gain or loss of electrons from the ligand set. While CoIII(isq)(ap) reacts with halide radicals to form a new cobalt-halide bond in a single electron reaction, [CoIII(ap)2]- appears to be prone to multi-electron reactivity in reactions with sources of "Cl+". Both reactions occur with electrons derived from the ligand set. Mechanistic studies suggest a single, two electron step is responsible for the bond-formation. Similarly, [CoIII(ap)2]- reacts with alkyl halides to pseudo-oxidatively add the alkyl at the cobalt center. The product of the reaction can be isolated and fully characterized and was found to be best assigned as CoIII(alkyl)(isq)2. This assignment indicates that the reaction occurs, again, with the new bond formed with two electrons formally derived from the ligand set and with no change in oxidation state at the metal center. Mechanistic investigations of the pseudo-oxidative addition suggest the reaction is SN2-like. The reaction occurs with a wide scope of alkyl halides, including those containing beta-hydrogens. : The cross-coupling reaction of CoIII(alkyl)(isq)2 with RZnX forms a new carbon-carbon bond. Similarly, the two electron oxidized complex [CoIII(CH3CN)(isq)2]+ reacts with organozinc reagents to couple two carbon nucleophiles and form a new carbon-carbon bond. Both reactions are successful with both sp2 and sp3 carbons. When followed substoichiometrically, the homocoupling reaction can be observed to form CoIII(alkyl)(isq)2. This indicates that the homocoupling and cross-coupling reactions proceed by the same mechanism. However, both reactions have low yields. The yield of the reactions are decreased by steric bulk of the alkyl or aryl fragments or around the metal center created by substituents on the ligand. Also, while the steric congestion disfavors the addition of the first alkyl fragment, the addition of the second alkyl fragment and subsequent rapid elimination of the coupling product is almost completely inhibited. This result also implies that the coupling of the two alkyl fragments is entirely inner-sphere requiring installation of both for coupling.
Synthesis and Structural Studies of Rhodium(III) and Cobalt(III) Complexes with Intramolecular Hydrogen Bonds
Author: Sutatip Siripaisarnpipat
Publisher:
ISBN:
Category :
Languages : en
Pages : 442
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 442
Book Description
Coordination Chemistry
Author: Stanley Kirschner
Publisher: Springer
ISBN: 1489965556
Category : Science
Languages : en
Pages : 355
Book Description
Publisher: Springer
ISBN: 1489965556
Category : Science
Languages : en
Pages : 355
Book Description
inorganic chemestry
Author:
Publisher: Rex Bookstore, Inc.
ISBN: 9789712346699
Category :
Languages : en
Pages : 732
Book Description
Publisher: Rex Bookstore, Inc.
ISBN: 9789712346699
Category :
Languages : en
Pages : 732
Book Description
Development Document for Effluent Limitations Guidelines
Author: United States. Environmental Protection Agency. Effluent Guidelines Division
Publisher:
ISBN:
Category : Fishery processing
Languages : en
Pages : 522
Book Description
Publisher:
ISBN:
Category : Fishery processing
Languages : en
Pages : 522
Book Description
EPA 440/1
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 350
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 350
Book Description