The structural rigidity of diamondoids and other cage-like molecules makes them ideal ‘molecular anvils’ to transduce external pressure into molecular-level strains. We synthesize structures containing compressible mechanophores and rigid ligands and show that hydrostatic pressure drives anisotropic deformation and redox reactions in these systems. This approach is uncovering new reaction mechanisms unavailable with conventional thermochemistry, and opens up new possibilities of realizing high-selectivity mechanochemistry for high-barrier reactions.
Image 1: Artist’s illustration of a molecular anvil structure being compressed in a diamond anvil cell. The relative motion of the rigid-cage ligands (blue and red) under hydrostatic pressure causes anisotropic strain in the soft mechanophore (purple and yellow), leading to reactions that are inaccessible in conventional thermochemistry. Image credit: Peter Allen@UCSB.
1. "Sterically controlled mechanochemistry under hydrostatic pressure." Hao Yan, Fan Yang, Ding Pan, Yu Lin, J. Nathan Hohman, Diego Solis-Ibarra, Fei Hua Li, Jeremy E. P. Dahl, Robert M. K. Carlson, Boryslav A. Tkachenko, Andrey A. Fokin, Peter R. Schreiner, Giulia Galli, Wendy L. Mao, Zhi-Xun Shen and Nicholas A. Melosh. Nature 554, pp. 505-510 (2018)