No abstract

The reaction of equal molar quantities of 1-methyl-3-ethylimidazolium chloride (MEICI) with AICI~ results in the formation of a conductive ambient-temperature ionic liquid that, when investigated voltammetrically, exhibits 4.4V of electroinactivity between the reduction of MEI + and the oxidation of AICI4-. When unequal quantities of these reagents are used, however, the resulting melt has a much narrower electrochemical window due either to the formation of the acid A12CIC (which reduces to A1 at potentials that are nearly 2.0V positive of MEI § reduction) or the base C1-(which oxidizes to C12 at potentials that are 1.5V negative of AICI(oxidation). In this paper we investigate those equilibrium processes that control the chloroacidity in these ionic liquids. Specifically, we show that they undergo an acid exchange reaction A1CI((I) + AICI((I) ~ AI2C17-(/) + CF(/) K = 1.0 x 10 -16

The reduction of diethyl fumarate (DEF) in tetra‐n‐butylammonium iodide (TBAI)‐dimethylformamide (DMF) solutions at a platinum electrode has been studied by cyclic voltammetry, double potential step chronoamperometry, and controlled potential coulometry. The chronoamperometric response for several possible mechanisms of electrohydrodimerization has been obtained by digital simulation techniques, and a method for distinguishing among the mechanisms suggested. Results of double potential step chronoamperometric experiments strongly support a mechanism where the electrochemically generated anion radicals undergo a second‐order dimerization reaction. Controlled potential electrolysis results give evidence for a bulk polymerization reaction in the absence of proton donor; protonation in the presence of hydroquinones; and good efficiency to the hydrodimer product in the presence of lithium perchlorate trihydrate.