Evidence for formation of ion pair stabilized diiodomethane radical anion in 1-butyl-3-methylimidazolium tetrafluoroborate room temperature ionic liquid

Voltammetric investigations on diiodomethane (CH2I2) in 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) are reported. Presented investigations show that, electroreduction of CH2I2 follows a typical irreversible redox behavior, where in initial electron transfer is the rate determining step. Electroreductive cleavage of carboniodine (CI) bond in CH2I2 is discussed in light of Marcus–Hush quadratic activation-driving force theory. The experimental findings establish that the dissociative electron transfer of CI bond in [BMIM][BF4] follows a stepwise pathway, which is a direct experimental evidence for formation of ion pair stabilized radical anion in RTIL. The reported results establish the role of RTILs in stabilization of electrogenerated intermediate and their subsequent chemistry in an electro-synthetic pathway.