Allosteric control of reaction thermodynamics is well understood but the mechanisms by which changes in local geometries of receptor sites lower activation reaction barriers in electronically uncoupled remote reaction moieties remain relatively unexplored. Here we report a molecular scaffold in which the rate of thermal E-to-Z isomerization of an alkene increases by a factor of as much as 10^4 in response to fast binding of a metal ion to a remote receptor site. A mechanochemi-cal model of the olefin coupled to a compressive harmonic spring reproduces the observed accel-eration quantitatively adding the studied isomerization to the very few reactions demonstrated to be sensitive to extrinsic compressive force. The work validates experimentally generalization of mechanochemical kinetics to compressive loads and demonstrates that the formalism of force-coupled reactivity offers a productive framework for the quantitative analysis of the molecular basis of allosteric control of reaction kinetics. Important differences in the effects of compressive vs. tensile force on the kinetic stabilities of molecules are discussed. The characterization and kinetic data generated in this study are deposited herein.
