Electrochemical and theoretical investigation of corannulene reduction processes.
The voltammetric generation of corannulene anions was investigated over a large range of experimental conditions comprising either "traditional" electrochemical solvents, such as dimethylformamide, acetonitrile, and tetrahydrofuran, or "unconventional" solvents, such as liquid ammonia, liquid methylamine, or liquid dimethylamine, and several different supporting electrolytes. Strong ion pairing effects were found to dominate the electrochemical generation of corannulene higher anions, and through the suitable choice of the solvent/electrolyte system, we observed, for the first time, the reversible electrochemical generation of up to the triply reduced corannulene. The standard potentials obtained experimentally compared rather well with the theoretical values calculated by ab initio and density functional methods, in which solvation and ion pairing effect were explicitly taken into account. In particular, the calculations considered the effect of the electrolyte cation size on ion pairing in order to rationalize the occurrence of the third reduction within the experimental potential window.
Bruno
Carlo
C
INSTM, Section of Bologna, and Dipartimento di Chimica G. Ciamician, Universita di Bologna, via Selmi 2, 40126 Bologna, Italy.
Benassi
Rois
R
Passalacqua
Alessio
A
Paolucci
Francesco
F
Fontanesi
Claudio
C
Marcaccio
Massimo
M
Jackson
Edward A
EA
Scott
Lawrence T
LT
D003198:Computer Simulation; D004563:Electrochemistry; D008956:Models, Chemical; D010084:Oxidation-Reduction; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry*
D011084:Polycyclic Aromatic Hydrocarbons; C434863:corannulene