Chiral catalysis with hybrid plasmonic nanoparticles

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Colloidal particles hold great potential for chiral catalysis due to their strong chiroptical effects and high catalytic activity. However, one of their key problems is the mismatch of scales between structural chiral features of the nanoparticles and the organic substrate. So far, the size of the structural chiral features of the catalyst—forming a so-called chiral bulk—needs to match to the size of the final product in order to to confer the chirality. This proposal aims at establishing a novel chiral catalyst based on hybrid plasmonic nanoparticles in dispersion. The proposed catalyst will be able to perform asymmetric C-C coupling reactions by transferring the required chiral bias via plasmonic field enhancement rather than by matching structural chirality, which is forming a steric bulk. Based on this mechanism, orthogonality in the catalytic asymmetric reaction can be achieved via altering of simple and reversible triggers—namely, the exchange of the chiral ligand or by changing the handedness of the exciting chiral light. Additionally, by exploiting plasmonics, the need of a matching chiral bulk is avoided, hence, giving rise to a broad range of targetable molecules featuring both, axial and stereogenic chirality. For this purpose, the hybrid nanoparticle system will be designed to combine the superior plasmonic quality of silver nanoparticles with the catalytic activity of platinum group metals. Thus, the plasmonics will not only confer the chirality to the substrate, but also boost the catalytic reaction by its strong electric field enhancement due to the envisioned core-shell particle design. During all stages of the project, the experimental work will be predicted and supported by modeling of electric fields and chiral properties via electro¬magnetic simulations aiming for a rational synthetic approach.