(711e) Self-Assembled Metal/Polymer Hybrid Nanoparticles and Their Use As Nanoreactors Towards Cascade Reactions

Confining reactions to hydrophobic microenvironments through the use of self-assembled amphiphilic molecules allows traditionally organic phase reactions to be carried out in a bulk aqueous phase. Replacing the organic solvent with these “nanoreactors” may reduce solvent waste. Flash NanoPrecipitation is a rapid, scalable, and modular method capable of continuously producing such structures. In this work, we use Flash NanoPrecipitation (FNP) as a platform technology to rapidly self-assemble kinetically trapped core-shell polymer nanoreactors that incorporate catalytic gold nanoparticles within tunable hydrophobic microenvironments and investigate their activity towards the reduction of 4-nitrophenol. Localized reagent solubility within the nanoreactors is investigated as the basis for composition-dependent activity differences with corresponding application to the Langmuir-Hinshelwood kinetic model. The partitioning of 4-nitrophenol between nanoreactor core compounds and water was found to vary by as much as two orders of magnitude, and when accounted for in Langmuir-Hinshelwood modeling resulted in individual nanoreactor kinetic activity parameters that fell within two-standard deviations of each other. This suggests that activity differences are the result of reagent solubility and not catalyst activity. Comparison between experimentally observed trends and Hansen Solubility Parameters will be discussed. Application of various nanoreactor systems to a reductive-amination cascade reaction will be presented. Preliminary results show approximately 50% in-situ yield of the desired product (4-benzylideneaminophenol). Green chemistry metrics, such as the E-factor, will be analyzed and discussed.