Gated molecular baskets

ORGN 288

Jovica D. Badjic, Department of Chemistry, The Ohio State University, 100 W. 18th Avenue, Columbus, OH 43210
It is still a great challenge to fundamentally address the relationship between structure and function in unnatural organic systems. Our approach consists of investigating the operation of folding molecules that are designed to perform useful functions. First, we have studied the working mechanisms of basket-like hosts capable to fold and thus incarcerate a guest. The folding process is mediated by intramolecular hydrogen bonding or metal-to-ligand coordination of the heterocyclic “flaps” appended to the basket rim. The incarceration of a guest is dictated by (a) its coordination to the metal cation, or (b) rapid opening and closing of the hydrogen bonding ‘flaps”. In this way, the guest exchange is restricted by the baskets' conformational behavior, which allows exploring the relationship between the molecular exchange kinetics and chemical reactions occurring in the confined space. Second, we have been developing molecular machines, “allosteric molecular resonators”, to investigate the controlled and synchronized motions of distant molecular parts in artificial systems. The constrictive binding, allostery and cooperativity have been altogether put at work for obtaining assemblies capable to perform complex operations. The lecture will focus on presenting our efforts in completing these endeavors.