Mechanical Activation of Microcycles

As an example of application of the gcw-dihalocyclopropane (gDHC) polymers, Craig and co-workers demonstrated that under the acoustic field generated by pulsed ultrasound (20 kHz and 11.9 W/cm ) trans gem-difiuorocyclopropane (gDFC) is mechanically forced to undergo the thermally forbidden comotatory 

Similarly, primarily because of the high inherent ring strain, the selective cleavage of a cyclobutane bond is facile, which makes cyclobutane and its derivatives promising mechanophores as well [98-101]. 

Successful applications of the macrocyclic force probes have been demonstrated in the kinetic study of mechanochemical reactions, especially multistep reactions. By incorporating an ester group in the stiff stilbene-based macrocycle, Boulatov and co-workers investigated its alkaline hydrolysis as a functimi of restoring force [110]. It was found that the hydrolysis of ester is insensitive to mechanical force, which is in agreement with MD simulations [112]. This is because the relative 

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