Atomically precise organomimetic cluster nanomolecules assembled via perfluoroaryl-thiol SNAr chemistry

Abstract

The majority of biomolecules are intrinsically atomically precise, an important characteristic that enables rational engineering of their recognition and binding properties. However, imparting a similar precision to hybrid nanoparticles has been challenging because of the inherent limitations of existing chemical methods and building blocks. Here we report a new approach to form atomically precise and highly tunable hybrid nanomolecules with well-defined three-dimensionality. Perfunctionalization of atomically precise clusters with pentafluoroaryl-terminated linkers produces size-tunable rigid cluster nanomolecules. These species are amenable to facile modification with a variety of thiol-containing molecules and macromolecules. Assembly proceeds at room temperature within hours under mild conditions, and the resulting nanomolecules exhibit high stabilities because of their full covalency. We further demonstrate how these nanomolecules grafted with saccharides can exhibit dramatically improved binding affinity towards a protein. Ultimately, the developed strategy allows the rapid generation of precise molecular assemblies to investigate multivalent interactions. The operational simplicity of modifying the surfaces of thiol-capped gold nanoparticles has been a hallmark of their success in materials chemistry, despite having limited control over the surface composition. Now, SNAr chemistry on activated perfluoroaromatics has been shown to mimic this simplicity and allow for the synthesis of atomically precise nanomolecules.