Mechanically Triggered Small Molecule Release from a Masked Furfuryl Carbonate
Stimuli-responsive polymers that release small molecules under mechanical stress are appealing targets for applications ranging from drug delivery to sensing. Here, we describe a modular mechanophore design platform for molecular release via a mechanically triggered cascade reaction. Mechanochemical activation of a furan–maleimide Diels–Alder adduct reveals a latent furfuryl carbonate that subsequently decomposes under mild conditions to release a covalently bound cargo molecule. The computationally guided design of a reactive secondary furfuryl carbonate enables the decomposition and release to proceed quickly at room temperature after unmasking via mechanical force. This general strategy is demonstrated using ultrasound-induced mechanical activation to release a fluorogenic coumarin payload from a polymer incorporating a chain-centered mechanophore.
Additional Information© 2019 American Chemical Society. Received: August 10, 2019; Published: September 13, 2019. Financial support from Caltech and the Dow Next Generation Educator Fund is gratefully acknowledged. We thank the Center for Catalysis and Chemical Synthesis of the Beckman Institute at Caltech for access to equipment and Larry Henling for assistance with X-ray crystallography. The authors declare no competing financial interests.
Supplemental Material - ja9b08663_si_001.pdf
Supplemental Material - ja9b08663_si_002.cif