OXIDATION–REDUCTION POLYMERS: III. STANDARD OXIDATION POTENTIALS OF 2,5-DIHYDROXYDIPHENYL SULPHONES

1964 ◽  
Vol 42 (3) ◽  
pp. 554-559 ◽  
Author(s):  
I. H. Spinner ◽  
H. P. Kasserra ◽  
W. Metanomski
Keyword(s):  
Oxidation Potentials ◽  
Oxidation Reduction ◽  
Derivatives Of

The preparation of two new sulphonyl derivatives of methoxy- and naphtha-hydroquinone as possible intermediate compounds in the synthesis of redox monomers is described. The standard oxidation potentials of these and other sulphonyl derivatives of hydroquinones were determined and compared with the values for similar compounds, reported previously (1).

scholarly journals 5-ACETYL-8-HYDROXYQUINOLINE AND 5-FORMYL-8- HYDROXYQUINOLINE: CHELATING AGENTS FOR COMPLEXOMETRIC TITRATIONS

2019 ◽  
Vol 16 (31) ◽  
pp. 765-777
Author(s):  
Roberto FERNANDEZ-MAESTRE ◽  
Alonso J MARRUGO-GONZÁLEZ
Keyword(s):  
Environmental Remediation ◽  
Chelating Agents ◽  
Organic Ligand ◽  
Formation Constants ◽  
Oxidation Reduction ◽  
Inductive Effects ◽  
Technological Developments ◽  
Metal Organic ◽  
Large Formation ◽  
Derivatives Of

Metal–organic ligand complexes are essential to many technological developments from protein supramolecular assemblies to solvent extraction, complexometric titrations, and environmental remediation. We studied the chelating and acid-base properties in ethanol of two derivatives of 8-hydroxyquinoline (Q), 5-acetyl-8-hydroxyquinoline (A) and 5-formyl-8-hydroxyquinoline (F), of which applications as chelators are unknown. The ligands acidity followed the order F (pKa1 2.9; pKa2 9.5)> A (pKa1 4.8; pKa2 9.6)> Q (pKa1 5.3; pKa2 10.0) due to inductive effects of electronegative groups, formyl in F and acetyl in A. The higher acidity of F with respect to A was due to the higher electronegativity of the formyl group in F. This acidity order was reflected in larger formation constants of F-metal complexes with pKf values of 32 (Fe3+), 27.1 (Cu2+), 26.2 (Cu2+), and 24.9 (Pb2+), than with A, with pKf values of 31, 22.5, 21.4 and 21.2 with these metals, or the pKf values in the literature for Q. In summary, A and F resulted excellent chelators for metals in complexometric titrations with large formation constants; these large formation constants recommend the application of these compounds in masking, preconcentration, and titration of metals by complexation and oxidation-reduction reactions.

Oxidation - Reduction Reactions of Tetrachloroaurate(III) Anion with Triphenyl Derivatives of Group V Elements

1973 ◽  
Vol 56 (7) ◽  
pp. 2405-2418 ◽  
Author(s):  
Raymond Roulet ◽  
Nguyen Quang Lan ◽  
W. Roy Mason ◽  
Gerald P. Fenske
Keyword(s):  
Group V ◽  
Reduction Reactions ◽  
Oxidation Reduction ◽  
Derivatives Of

Oxidation Potentials of N-Modified Derivatives of the Analgesic Flupirtine Linked to Potassium KV7 Channel Opening Activity But Not Hepatocyte Toxicity

ChemMedChem ◽  
2014 ◽  
Vol 10 (2) ◽  
pp. 368-379 ◽  
Author(s):  
Christian J. Lemmerhirt ◽  
Mirko Rombach ◽  
Anja Bodtke ◽  
Patrick J. Bednarski ◽  
Andreas Link
Keyword(s):  
Oxidation Potentials ◽  
Channel Opening ◽  
Derivatives Of ◽  
Hepatocyte Toxicity

OXIDATION–REDUCTION POLYMERS: II. STANDARD OXIDATION POTENTIALS OF REDOX HOMOPOLYMERS AND THEIR MONOMERIC MODELS

1963 ◽  
Vol 41 (2) ◽  
pp. 483-494 ◽  
Author(s):  
I. H. Spinner ◽  
W. D. Raper ◽  
W. Metanomski
Keyword(s):  
Model Compounds ◽  
Oxidation Potentials ◽  
Oxidation Reduction ◽  
The One

A new monomer, 2,5-bis-(2-tetrahydropyranyloxy)-4-methyl-4′-vinyldiphenyl sulphone, has been prepared. The standard oxidation potentials of two linear redox homopolymers, derived from this monomer and the one previously reported (1), and of their intermediate and model compounds, have been measured using continuous and discontinuous titration techniques.

Theoretical study of the electron structure and properties of dithiocarbamates and their complexes with transition metals

1984 ◽  
Vol 49 (12) ◽  
pp. 2744-2750 ◽  
Author(s):  
Stanislav Miertuš ◽  
Vladimír Frecer
Keyword(s):  
Transition Metals ◽  
Theoretical Study ◽  
Electron Structure ◽  
Structure And Properties ◽  
Spin Multiplicity ◽  
Model Complexes ◽  
Oxidation Reduction ◽  
Bonding Properties ◽  
Derivatives Of

The semiempirical CNDO/2 method was used to calculate the electron structure of derivatives of dithiocarbamates, R2N-CS2, as anions and radicals. We studied changes in the oxidation-reduction and bonding properties by changes of R = H, CH2, C2H5, C3H5. Calculations were also carried out on model complexes of R2N-CS2 with metals Cu, Mn, Fe, Co, Ni. Differences in the electron structure of these complexes with various numbers of ligands, various states of oxidation and varying spin multiplicity of the central atoms were evaluated.

METALLOCENE CHEMISTRY—A DECADE OF PROGRESS

1963 ◽  
Vol 41 (5) ◽  
pp. 1289-1314 ◽  
Author(s):  
M. D. Rausch
Keyword(s):  
Transition Metals ◽  
Arene Complexes ◽  
Aromatic System ◽  
Substitution Reactions ◽  
The Past ◽  
Orientation Effects ◽  
Oxidation Reduction ◽  
Carbonium Ions ◽  
Rearrangement Reactions ◽  
Derivatives Of

One of the most significant new frontiers in chemistry during the past decade has been the stabilization and study of π-organic derivatives of the transition metals. Over 60 elements are now known to form one or more cyclopentadienyl compounds. The aromatic-type reactions displayed by ferrocene and related complexes have also been extensively investigated. Ferrocene will undergo alkylation, acylation, sulphonation, metalation, arylation, formylation, aminomethylation, and other reactions characteristic of a highly reactive aromatic system. π-Cyclopentadienyl derivatives of vanadium, chromium, manganese, ruthenium, and osmium as well as certain π-arene complexes of chromium exhibit ring substitution reactions in varying degrees. Other metallocenes undergo ring addition reactions.The orientation effects of substituents on reactions of substituted ferrocenes have been studied. A variety of unique oxidation, reduction, dehydration, and rearrangement reactions are known in metallocene chemistry. Haloferrocenes and mercuriferrocenes are readily converted to biferrocenyl. Recent rate investigations have established that carbonium ions adjacent to metallocene nuclei possess unusual stabilization as a result of direct metal participation.

β-Nitro-substituted free-base, iron(III) and manganese(III) tetraarylporphyrins: synthesis, electrochemistry and effect of the NO2 substituent on spectra and redox potentials in non-aqueous media

2013 ◽  
Vol 17 (08n09) ◽  
pp. 857-869 ◽  
Author(s):  
Shuibo Yang ◽  
Bin Sun ◽  
Zhongping Ou ◽  
Deying Meng ◽  
Guifen Lu ◽  
...  
Keyword(s):  
Aqueous Media ◽  
Redox Potentials ◽  
Free Base ◽  
Absorption Bands ◽  
H Nmr ◽  
Oxidation Potentials ◽  
Visible Spectra ◽  
Phenyl Rings ◽  
Metal Derivatives ◽  
Derivatives Of

Two free-base and four metal derivatives of substituted tetraarylporphyrins containing a nitro-substituent on the β-pyrrole position of the macrocycle were synthesized and characterized by UV-vis, FTIR, 1 H NMR and mass spectrometry as well as electrochemistry and spectroelectrochemistry in non-aqueous media. The porphyrins are represented as ( NO 2 TmPP ) M and ( NO 2 TdmPP ) M , where M = 2 H , Fe III Cl or Mn III Cl , m is a CH 3 group on the para-position of the four meso-phenyl rings of the tetraphenylporphyrin (TPP) and dm represents two OCH 3 substituents on the meta-positions of each phenyl ring of the TPP macrocycle. UV-visible spectra of the nitro-substituted porphyrins exhibit absorption bands which are red-shifted by 4–11 nm as compared to bands of the same substituted tetraarylporphyrins lacking a nitro substituent. Three or four reductions are observed for each iron and manganese nitroporphyrin, the first of which is metal-centered, leading to formation of an Fe ( II ) or Mn ( II ) complex. Further reduction at the metal center occurs for the iron porphyrins but this reaction proceeds via an Fe ( II ) π anion radical in the case of the two nitro-substituented derivatives. The β-nitro-substituted porphyrins are easier to reduce and harder to oxidize than the corresponding compounds lacking a nitro group. The effect of NO 2 substituent on reduction/oxidation potentials and the site of electron transfer was also discussed.

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