Author: Keith Lawrence Scott
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The Preparation and Characterisation of Carboxylato-bridged Cobalt (III) Complexes and the Kinetics of Reduction by Chromium (II) and Vanadium (II).
Author: Keith Lawrence Scott
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Preparation, Characterization, and Kinetics and Mechanisms of the Chromium (II) Reduction of O-bonded L-cysteinepentaammine-Cobalt (III) Perchlorate
Author: John S. Cardwell
Publisher:
ISBN:
Category : Chromium
Languages : en
Pages : 142
Book Description
Publisher:
ISBN:
Category : Chromium
Languages : en
Pages : 142
Book Description
American Doctoral Dissertations
Author:
Publisher:
ISBN:
Category : Dissertation abstracts
Languages : en
Pages : 728
Book Description
Publisher:
ISBN:
Category : Dissertation abstracts
Languages : en
Pages : 728
Book Description
The Preparation, Characterization, and Chromium (II) Reduction of Pentaamminecobalt (III)
Author: Robert J. Balahura
Publisher:
ISBN:
Category : Chormium
Languages : en
Pages : 0
Book Description
The chromium(II) reduction of a series of pentaammine- cobalt(III) complexes has been studied. A classification into inner- or outer-sphere paths has been made and the position of attack of the reductant on the ligand determined. The oxygen-bonded complexes of formamide, N,N-dimethylform- amide, dimethylsulfoxide, and urea as well as the nitrogen bonded N-cyanoguanidine complex are reduced by means of an outer-sphere mechanism. On the other hand ligand transfer was shown to occur in the reduction of (NH[subscript 3])[subscript 5]CoNHCHO[superscript 2+], (NH[subscript 3])[subscript 5]CoNCNH[superscript 2+], (NH[subscript 3])[subscript 5]CoO[subscript 2]CNH[subscript 2][superscript 2+], (NH[subscript 3])[subscript 5]CoO[subscript 2]CC[subscript 6]H[subscript 4]CN[superscript 2+], and (NH[subscript 3])[subscript 5]CoNCO[superscript 2+]. Both outer- and inner-sphere paths operate in the reduction of the nitrile bonded 4-cyanophenol complex, the inner-sphere path comprising 20% of the overall reaction. For the reduction of the terephthalonitrile complex a classification into an inner- or outer-sphere path cannot be made/ and an outer-sphere electron transfer to the ligand is postulated as the rate-determining step. A large part of the work has been concerned with the characterization of the complexes and Chapter III describes the spectroscopic measurements undertaken as well as the chemical reactions of some of the complexes. The acid dissociation constant of the N isomer of formamidopentaamine- cobalt(III), cyanamidopentaamminecobalt(III), and the nitrile bonded 4-cyanophenol have been determined. The protonation equilibrium constant for carbamatopentaammine- cobalt(III) was also obtained. A kinetic study of the acid hydrolysis of isocyanatopentaamminecobalt(III) to form hexaamminecobalt(III) and carbon dioxide was carried out. The acylation of the cyanamide and 4-cyanophenol complexes was also studied. The results of the kinetic studies of the chromium(II) reductions indicate a possible correlation between the reduction rate and the half-wave potential for the reduction of the free ligand. The studies have led to the following generalizations regarding electron transfer reactions: (1) attack of reductant at a coordinated atom does not occur, (2) the atom attached to chromium(II) in the transition state must have two lone pairs of electrons, and (3) the reducibility of the complexed ligand plays an important role in the detailed mechanism for the transfer of the electron.
Publisher:
ISBN:
Category : Chormium
Languages : en
Pages : 0
Book Description
The chromium(II) reduction of a series of pentaammine- cobalt(III) complexes has been studied. A classification into inner- or outer-sphere paths has been made and the position of attack of the reductant on the ligand determined. The oxygen-bonded complexes of formamide, N,N-dimethylform- amide, dimethylsulfoxide, and urea as well as the nitrogen bonded N-cyanoguanidine complex are reduced by means of an outer-sphere mechanism. On the other hand ligand transfer was shown to occur in the reduction of (NH[subscript 3])[subscript 5]CoNHCHO[superscript 2+], (NH[subscript 3])[subscript 5]CoNCNH[superscript 2+], (NH[subscript 3])[subscript 5]CoO[subscript 2]CNH[subscript 2][superscript 2+], (NH[subscript 3])[subscript 5]CoO[subscript 2]CC[subscript 6]H[subscript 4]CN[superscript 2+], and (NH[subscript 3])[subscript 5]CoNCO[superscript 2+]. Both outer- and inner-sphere paths operate in the reduction of the nitrile bonded 4-cyanophenol complex, the inner-sphere path comprising 20% of the overall reaction. For the reduction of the terephthalonitrile complex a classification into an inner- or outer-sphere path cannot be made/ and an outer-sphere electron transfer to the ligand is postulated as the rate-determining step. A large part of the work has been concerned with the characterization of the complexes and Chapter III describes the spectroscopic measurements undertaken as well as the chemical reactions of some of the complexes. The acid dissociation constant of the N isomer of formamidopentaamine- cobalt(III), cyanamidopentaamminecobalt(III), and the nitrile bonded 4-cyanophenol have been determined. The protonation equilibrium constant for carbamatopentaammine- cobalt(III) was also obtained. A kinetic study of the acid hydrolysis of isocyanatopentaamminecobalt(III) to form hexaamminecobalt(III) and carbon dioxide was carried out. The acylation of the cyanamide and 4-cyanophenol complexes was also studied. The results of the kinetic studies of the chromium(II) reductions indicate a possible correlation between the reduction rate and the half-wave potential for the reduction of the free ligand. The studies have led to the following generalizations regarding electron transfer reactions: (1) attack of reductant at a coordinated atom does not occur, (2) the atom attached to chromium(II) in the transition state must have two lone pairs of electrons, and (3) the reducibility of the complexed ligand plays an important role in the detailed mechanism for the transfer of the electron.
The Synthesis, Characterization and Chromium (II) Reduction of Cobalt (III) Complexes Containing Thiolate, Alcoholate and Thioether Residues
Author: Michael James Gilroy
Publisher:
ISBN:
Category : Chromium
Languages : en
Pages : 174
Book Description
Publisher:
ISBN:
Category : Chromium
Languages : en
Pages : 174
Book Description
The Reduction of Carboxylatopentaamminecobalt (III) Complexes by Chromium (II) and Vanadium (II) Ions
Author: Martha An Barcalow Barrett
Publisher:
ISBN:
Category : Metal ions
Languages : en
Pages : 222
Book Description
Publisher:
ISBN:
Category : Metal ions
Languages : en
Pages : 222
Book Description
Quarterly Journal of the Chemical Society of London
Author: Chemical Society (Great Britain)
Publisher:
ISBN:
Category : Chemistry
Languages : en
Pages : 1326
Book Description
Publisher:
ISBN:
Category : Chemistry
Languages : en
Pages : 1326
Book Description
Comprehensive Dissertation Index
Author:
Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 754
Book Description
Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 754
Book Description
Dissertation Abstracts International
Author:
Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 1396
Book Description
Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 1396
Book Description
Comprehensive Dissertation Index: Chemistry, P-Z
Author:
Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 844
Book Description
Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 844
Book Description