POLYETHYLENEGLYCOL-CATALYZED BENZIL BENZILIC ACID REARRANGEMENT - A REACTION IN SOLUBLE MACROMOLECULAR CAVITIES

Kinetics of benzil-benzilic acid rearrangement was investigated in the presence of polyethyleneglycols (PEG) at different concentrations. PE G of molecular weights 400 and 6000 were used for the studies. A set o f solutions was prepared with varying PEG contents. The rearrangment w as carried out in these systems and the rate constants were calculated . The rates surprisingly increased with PEG content instead of decreas ing due to the reduced ionic movement in these viscous macromolecular solutions. In the presence of KOH and NaOH, PEG acts as a catalyst for the rearrangement. But in presence of LiOH, an inverse relation was o bserved between PEG content and the rate of reaction. These observatio ns were explained on the basis of the cation-binding ability of polyet hyleneglycols.