Solvent Effects on the Kinetics of Epoxide Carbonation in Dihydroxyethyldiethylammonium Bromide Ionic Liquids.

Solvent effects by ionic liquids (ILs) may be assessed by using a complementary supermolecule + dielectric continuum approach. We revisited the carbonation mechanism of epoxide in the [Net₂(HE)₂][Br] ionic liquid and found that the reaction field (RF) effect in the outer sphere of solvation determines the accepted mechanism for the title reaction. This implicit solvent effect appears to be related to the maximum hardness principle (MHP) involving the relative energy/hardness relationship at the transition-state structures: a highly encouraging result, as it suggests that classical reactivity rules could still be applied in the presence of complex ionic environments.