Reactions+of+Mechanism



a - Protonation of DBU in the presence of an alcohol and C02 is reversed when C02 is removed.

b - Polarity switching in which C02 causes a nonpolar liquid (blue) mixture of hexanol and DBU to change into a polar, ionic liquid (red). N2 reverses the process by removing C02 from the reaction.

c - The different polarity of each liquid under the two conditions is shown by the miscibility of decane with the hexanol/DBU mixture under nitrogen, before exposure to C02. But, decane seperates out when the mixture becomes polar in the presence of C02. And again, N2 reverses the process.

Source: Jessop, P. G.; Heldebrant, D. J.; Xiaowang, L.; Eckert, C. A.; Liotta, C. L. Reversible Nonpolar-to-polar Solvent. //Nature// [online] **2005**, //436//, 1102. http://www.nature.com.ezproxy.lib.ucalgary.ca/nature/journal/v436/n7054/full/4361102a.html (accessed Oct. 1. 2011)