Mechanochemical Release of N-Heterocyclic Carbenes from Flex-Activated Mechanophores

We have discovered a new flex-activated mechanophore that releases an N-heterocyclic carbene (NHC) under mechanical load. The mechanophore design is based upon NHC-carbodiimide (NHC-CDI) adducts and demonstrates an important first step toward flex-activated designs capable of further downstream reactivities. Since the flex-activation is non-destructive to the main polymer chains, the material can be subjected to multiple compression cycles to achieve iterative increases in the activation percentage of mechanophores. Two different NHC structures were demonstrated, signifying the potential modularity of the mechanophore design.

Automated summary

A new flex-activated mechanophore has been discovered, which releases an N-heterocyclic carbene (NHC) under mechanical load. This design demonstrates a promising first step towards flex-activated designs with downstream reactivities, allowing for iterative activation increases in the material through non-destructive compression cycles. The potential modularity of the mechanophore design is highlighted by the demonstration of two different NHC structures.