While much progress has been made towards understanding the role of mechanical forces in accelerating and directing purely covalent chemical reactivity, the behavior of coordinative complexes subjected to the same is far less understood. To probe the effect of mechanical forces on the behavior of coordination complexes, we have designed and synthesized novel metallomechanophore constructs containing ligands intimately connected within polymer chains and subjected them to mechanical force either by single molecule force spectroscopy (SMFS) or shear forces in solution. It is anticipated that mechanical force can distort the coordination environment about a metal center in ways that access unique structural, electronic, and reactivity profiles unattainable in force-free conditions. We expect to identify force regimes that persist prior to metal decomplexation or covalent bond scission, signaling intermediates of altered coordination environment under mechanical strain. These results will establish a roadmap for accessing strained metal coordination complexes that would enable unique physical and chemical properties of metal complexes to be leveraged for creating novel stress-responsive materials. Our current work has focused on using multiple synthetic techniques to incorporate high loadings of the molecule of interest into a polymer of sufficient molecular weight for SMFS or sonochemical testing and determining the best methods for monitoring changes of the metallopolymer. Future work will include testing different metals, different oxidation states, and different complex geometries to see how force changes these metal-ligand interactions.

Metal coordination complexes in mechanically responsive systems

254th National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.