Steric Barrier-Steered Reaction Sites in Micellar Catalysis

摘要

In the pursuit of an advanced micellar catalysis system, the reaction sites inmicelles determine its catalytic performances. However, the intrinsic polaritygradient of micelles anchors the reactants in the fixed regions, leading to anunmet challenge to steer the reaction sites to the optimal ones. To overcomethis limitation, a F?rster resonance energy transfer (FRET) spectroscopic ruleris established to position the true sites of reactants in micellar catalysis byusing tetraphenylethylene (TPE) in the aggregation-induced emission (AIE)micelles as the FRET donor and Nile red as the FRET acceptor. Subsequently,the customizable TPE steric barriers in the AIE micelles are apt to mediatethe reactants into the polar micellar surface, the semipolar palisade layer, orthe nonpolar internal layer, achieving the corresponding catalytic efficiencies.Additionally, the universality of steric barrier-steered reaction sites inmicellar catalysis is further demonstrated by the simple incorporation ofsmall nonpolar molecules into the commercially available surfactants. To theauthors’ knowledge, this is the first report on the design of steric barriers tosteer the reaction sites in micellar catalysis. These findings open up attractiveperspectives for the exploration of new classes of efficient micellar catalysissystems in a variety of reactions.