Electrosynthesis in systems of two immiscible liquids and a phase transfer catalyst. II. Aromatic nuclear acyloxylation

It was demonstrated that the principles of ion pairing could be used to predict the effect of a quaternary ammonium salt on the rate of electrodeposition of several metals. In agreement with prediction the cationic surfactant, in general, appreciably increased the limiting current, the current efficiency, and the percentage composition in alloys of metals deposited from negative ions in solution while decreasing slightly the same factors for metals deposited from positive ions in solution. It was also shown that there are predictable situations in which the ion paired acceleration would not be observed when expected. Those situations are: (1) processes not limited by the rate of adsorption; (2) processes in which the rate is limited by reaction with a species different from the predominant negatively charged species; and (3) processes in which a film is formed on the electrode.

Section: Discussionmentioning

confidence: 99%

Ion Pairing as a Mechanism of Action of Additives in Electrodeposition

Franklin

Totten

Aktan

1988

“…Phase transfer agents serve to catalyze the reaction by transferring one reactant across the interface into the other phase where the reaction will proceed. The work of Eberson and Helgee (20)(21)(22)(23) and Ellis and Pletcher (24) have shown that the yields of the desired product can be markedly increased through the use of phase transfer agents. *Electrochemical Society Active Member.…”

mentioning

confidence: 99%

Investigation of Mass Transfer by Diffusion in Two‐Phase Electrolytes

Moreland

Fenton

1989

The effect of a two-phase electrolyte on diffusion of reactants to a horizontal planar electrode in quiet solution was investigated. Three systems were studied; ferricyanide reduction from basic aqueous solution, ferricyanide reduction from basic aqueous solution with an inert drop of methylene chloride on the electrode, and iodine reduction from aqueous solution with a drop of methylene chloride containing a high concentration of iodine on the electrode. Experiments were conducted with controlled variation of reactant concentration, drop size, number of drops, and electrode area. It was found that with the addition of an inert drop, the reaction rate decreased proportionally to the drop contact area, while the reaction rate increased substantially with the addition of a drop containing a high concentration of iodine.

“…A study was initiated on the use of ion-pairing as a different method of controlling the composition of electrodeposited alloys. Ion-pairing is a widely used technique for accelerating many reactions in organic (2,3), electroorganic (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19), and electro-inorganic chemistry (13,14,(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30). In all of these applications, the reactions are accelerated by extracting an ion from a high dielectric constant medium (an aqueous system) to a low dielectric constant medium [a nonpolar organic system or the electrode interface (31)] by the formation of an ion-pair that is more stable in the low dielectric constant medium.…”

mentioning

confidence: 99%

Ion Pairing as a Method of Controlling the Composition of Electrodeposited Alloys

Franklin

Darlington

Fierro

1986

A study was made of the possibility of controlling the composition of electrodeposited alloys by the use of noncomplexing ion‐pairing salts. It was shown both voltammetrically and by analysis of electrodeposits that the addition of ion‐pairing cations increased the rate of deposition of tin significantly (because of ion‐pairing with the negative stannite or stannate ion) and slightly decreased the rate of deposition of the positively charged copper. As a consequence of this, the addition of tetrabutylammonium perchlorate increased the ratio of tin to copper in the deposit. The lowering of the dielectric constant of the solution by addition of tert‐butyl alcohol increased the ion‐pairing and, thus, increased this effect. Similarly, it was shown that the quaternary salt increased the current efficiency for deposition of tin and slightly decreased the current efficiency for deposition of copper.