Force-Accelerated Ring Opening of Episulfide by Pulsed Ultrasonication

Covalent polymer mechanochemistry is an emerging field that leverages the mechanical force transduced by polymer chains to bias or alter the reaction pathways uniquely, thereby influencing the stereoselectivity of chemical transformations. This study investigates the mechanochemical reactivities of episulfides featuring alkyl, ester, and phenyl substituents under pulsed ultrasonication, and the results demonstrate that episulfides bearing alkyl and phenyl substituents can undergo C-C bond cleavage to produce reactive intermediates that are amenable to subsequent <i>cis</i>-<i>trans</i> isomerization and cycloaddition reactions. In contrast, the episulfide with ester substituents is mechanochemically inactive.