scholarly journals Electropolymerization of N,N'-Diphenylguanidine in Non-Aqueous Aprotic Solvents and Alcohols

2020 ◽  
Vol 65 (1) ◽  
pp. 139-147
Author(s):  
László Kiss ◽  
Ferenc Kovács ◽  
Sándor Kunsági-Máté
Keyword(s):  
Cyclic Voltammetry ◽  
Dimethyl Sulfoxide ◽  
Benzyl Alcohol ◽  
Polymer Films ◽  
Platinum Electrode ◽  
Anodic Peak ◽  
Dimethyl Formamide ◽  
Aprotic Solvents ◽  
Permeability Studies ◽  
Voltammetric Peak

Electrooxidation of N,N’-diphenylguanidine (1,3-diphenylguanidine) was investigated in aprotic (acetonitrile, acetone, dimethyl sulfoxide, dimethyl formamide, propyleneoxide, nitromethane) and alcoholic (methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, benzyl alcohol) non-aqueous solvents at platinum electrode with cyclic voltammetry. Its concentration was 5 mM in most cases. In acetonitrile and acetone a sharp voltammetric peak appeared around 1 V vs. reference and currents measured in the subsequent scans showed that the electrode fouled quickly. In dimethyl formamide, the anodic peak heights decreased slowly in the subsequent scans but in dimethyl sulfoxide weak deactivation could be observed both in smaller and in higher concentration. In alcohols, continuous deactivation could be also observed during electrooxidation of N,N’-diphenylguanidine. The permeability studies showed that the structure of the formed polymer films varied significantly according to the solvent used for electrodeposition.

Ligand substitution kinetics of iron(III) in aprotic solvents

1983 ◽  
Vol 36 (5) ◽  
pp. 843 ◽  
Author(s):  
JT Carr ◽  
PA Treloan
Keyword(s):  
Ionic Strength ◽  
Dimethyl Sulfoxide ◽  
Activation Parameters ◽  
Forward Rate ◽  
Dimethyl Formamide ◽  
Activation Entropy ◽  
Aprotic Solvents ◽  
Forward Rate Constant ◽  
Temperature Activation ◽  
Complexation Reactions

The complexation reactions of NCS- and Br- with iron(III) have been studied in N,N-dimethyl-formamide, and the temperature activation parameters determined. The observed forward rate constants are 114±5 and 69±31, mol-1 s-1, the activation enthalpies are 48+±3 and 74±4 kJ mol-1, and the activation entropies are -45±8 and 40±10 J K-1 mol-1, respectively, at 298 K and 0.5 M ionic strength. The complexation reactions of NCS- with iron(III) in dimethyl sulfoxide have been studied at ionic strengths of 0.1, 0.3 and 0.5 M, and over a range of temperatures. The observed forward rate constant is 55±31. Mol-1 s-1, the activation enthalpy is 42±3 kJ mol-1, and the activation entropy is -70±30 J K-1 mol-1 at 298 K and 0.5 M ionic strength. It is proposed that the substitution reactions of iron(111) in the aprotic solvents N,N-dimethyl- formamide and dimethyl sulfoxide proceed through an associative interchange (Ia) mechanism.

Endgroup and Sidechain Functionalization of Surface-Initiated ROMP Thin Films: Progress Towards ROMP-Based Molecular Wires

2018 ◽  
Author(s):  
Nicholas Marshall
Keyword(s):  
Thin Films ◽  
Contact Angle ◽  
Cyclic Voltammetry ◽  
Polymer Films ◽  
Conjugated Polymer ◽  
Ring Opening ◽  
Molecular Wires ◽  
Metathesis Polymerization ◽  
Cross Metathesis ◽  
Active Ester

A set of experiments in surface-initiated ring-opening metathesis polymerization, including end-functionalization of growing brushes and contact angle/cyclic voltammetry measurements. We report preparation and CV of two different conjugated polymer films, and several endgroup and sidechain functionalization experiments using cross-metathesis and active ester substitution.<br>

A cyclic voltammetry study of the adsorption of alcohol dehydrogenase (HLADH) onto a platinum electrode

2000 ◽  
Vol 2 (11) ◽  
pp. 805-809 ◽  
Author(s):  
Ralph K.R Phillips ◽  
Sasha Omanovic ◽  
Sharon G Roscoe
Keyword(s):  
Cyclic Voltammetry ◽  
Alcohol Dehydrogenase ◽  
Platinum Electrode

Solvation of the halide anions in dimethyl sulfoxide. Factors involved in enhanced reactivity of negative ions in dipolar aprotic solvents

1984 ◽  
Vol 106 (21) ◽  
pp. 6140-6146 ◽  
Author(s):  
Tom F. Magnera ◽  
Gary Caldwell ◽  
Jan Sunner ◽  
Sigeru Ikuta ◽  
Paul Kebarle
Keyword(s):  
Dimethyl Sulfoxide ◽  
Negative Ions ◽  
Aprotic Solvents ◽  
Halide Anions ◽  
Dipolar Aprotic Solvents

Electron-transfer reactions in non-aqueous media. VII. Reduction of CoF(NH3)52+ and Co(HCOO)(NH3)52+ by copper(I) in dimethyl sulfoxide-water mixtures

1983 ◽  
Vol 36 (10) ◽  
pp. 1923 ◽  
Author(s):  
JMB Harrowfield ◽  
L Spiccia ◽  
DW Watts
Keyword(s):  
Electron Transfer ◽  
Dimethyl Sulfoxide ◽  
Aqueous Media ◽  
Mixed Solvents ◽  
Transfer Reactions ◽  
Aprotic Solvents ◽  
Aqueous Mixtures ◽  
Electron Transfer Reactions ◽  
Dipolar Aprotic Solvents ◽  
Sphere Mechanism

Previous work on the reduction of a series of cobalt(III) complexes by iron(II) in dipolar aprotic solvents and in aqueous mixtures has been extended to reduction by copper(I). The greater stability of copper(I) to disproportionation in these media has permitted the study of the reduction of CoF(NH3)52+ and Co(HCOO)(NH3)52+ in range of solvents over a number of temperatures with a precision not possible in previous studies in water. The results are consistent with an inner-sphere mechanism in which the copper(I) reductant is preferentially solvated by dimethyl sulfoxide to the exclusion of water in mixed solvents.

scholarly journals Effect of Anodic Pretreatment on the Performance of Glassy Carbon Electrode in Acetonitrile and Electrooxidation of Para-substituted Phenols in Acetonitrile on Platinum and Glassy Carbon Electrode

2019 ◽  
Vol 65 (1) ◽  
pp. 133-138 ◽  
Author(s):  
László Kiss ◽  
Sándor Kunsági-Máté
Keyword(s):  
Glassy Carbon Electrode ◽  
Glassy Carbon ◽  
Electrode Surface ◽  
Platinum Electrode ◽  
Anodic Peak ◽  
Carbon Electrode ◽  
Substituted Phenols ◽  
Cyclic Voltammetric ◽  
Pretreatment Time

In the first part of the work electropolymerisation of phenol was studied at glassy carbon electrode. Rapid fouling of its surface indicated the formation of coherent poly(phenyleneoxide) layer which was demonstrated by the repeated cyclic voltammetric scans. Effect of anodic pretreatment potential in acetonitrile solvent was also investigated and the results showed that at potentials higher than 2 V glassy carbon electrode becomes deactivated. Preanodisation of glassy carbon electrode at 3 V in acetonitrile resulted in diminished anodic peak currents by phenols. It was due to the partial deactivation of electrode surface and its extent increased with the pretreatment time. The electrooxidation of para-substituted phenols (p-Cl-phenol, p-NO2-phenol, p-tertbutylphenol, p-methoxyphenol) in acetonitrile resulted in no fouling layer on platinum electrode and the peak currents were significantly higher than in the first scan of unsubstituted phenol in the same concentration. Glassy carbon deactivated continuously by repeating the scans due to the solvent and bonding of products on the surface.

Dimethyl sulfoxide and dimethyl formamide increase lifespan of C. elegans in liquid

2013 ◽  
Vol 134 (3-4) ◽  
pp. 69-78 ◽  
Author(s):  
Harald Frankowski ◽  
Silvestre Alavez ◽  
Patricia Spilman ◽  
Karla A. Mark ◽  
Joel D. Nelson ◽  
...  
Keyword(s):  
Dimethyl Sulfoxide ◽  
Dimethyl Formamide ◽  
C Elegans

scholarly journals Electrochemical Trifluoromethylation of Isonicotinic acid hydrazide using Cyclic Voltammetry and Galvanostatic Electrolysis

2018 ◽  
Vol 34 (4) ◽  
pp. 2098-2105
Author(s):  
Raja Beryl J ◽  
Joseph Raj Xavier
Keyword(s):  
Cyclic Voltammetry ◽  
Glassy Carbon ◽  
Current Density ◽  
Platinum Electrode ◽  
Isonicotinic Acid ◽  
Acid Hydrazide ◽  
Isonicotinic Acid Hydrazide ◽  
Glassy Carbon Electrodes ◽  
Galvanostatic Electrolysis ◽  
Sodium Trifluoroacetate

Trifluoromethylation of isonicotinic acid hydrazide has been investigated in trifluoroacetic acid containing pyridine, triethylamine and sodium trifluoroacetate dissolved in acetonitrile on platinum and glassy carbon electrodes using cyclic voltammetry. LSVs for isonicotinic acid hydrazide in 0.1 M TFA/ Py/TEA/NaTFA in acetonitrile on platinum electrode show that there is no distinct oxidation peak for the oxidation of isonicotinicacid hydrazide within the voltammetric region of 0.0 to 1.6 V vs Ag and it gets oxidized anodically in the gas evolution region itself. TFA/ NaTFA medium shows slightly higher current density than the other two media for the oxidation of isonicotinic acid hydrazide. CVs for different concentrations of isonicotinic acid hydrazide show that anodic peak becomes broad and flat. It shows that severe adsorption of INAH/product takes place on the glassy carbon electrode during the voltammetry scanning. Galvanostatic electrolysis of INAH in TFA/Py/ACN medium at low current density on Pt shows good conversion with low selectivity.

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