Aqueous Micelles as Catalytic Nanoreactors for Dephosphorylation Reactions

The reaction of a new imidazole derivative, 3,5-bis((1H-imidazol-1-yl)methyl)aniline (BIm), and the model triester diethyl 2,4-dinitrophenyl phosphate (DEDNPP), which proceeds via a S_N2(P) mechanism, is substantially enhanced in the presence of either cationic cetyltrimethylammonium bromide (CTAB) or anionic sodium dodecyl sulfate (SDS). This unusual micellar effect illustrates the use of the hydrophobic character of the reactants to enhance micellar catalysis. This is an important and useful guideline in planning mimics for biological reactions, because improving incorporation will increase the quality of the biomimetic systems, and both cationic or anionic surfactants will act as homogeneous nanoreactors concentrating the neutral, hydrophobic reactants.

dephosphorylation; imidazole; nucleophilic catalysis; micellar catalysis