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Updated: Mar 14, 2026
09:43
A Protocol for Using Förster Resonance Energy Transfer (FRET)-force Biosensors to Measure Mechanical Forces across the Nuclear LINC Complex
Published on: April 11, 2017
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Unveiling Orthogonal Mechanochemical Pathways via 19F NMR under a Three-Arm Pulling Strategy.
Deao Xu1, Cichang Ling1, Hanwen Qu1
1Department of Macromolecular Science, State Key Laboratory of Molecular Engineering of Polymers, Fudan University, 200438 Shanghai, China.
Journal of the American Chemical Society
|March 12, 2026
Summary
This study introduces a novel fluorinated mechanophore activated by three-arm pulling, enabling two simultaneous chemical reactions. This multi-pathway approach expands the possibilities for force-responsive molecular design.
Area of Science:
- Polymer Science
- Organic Chemistry
- Materials Science
Background:
- Polymer mechanochemistry uses force to control chemical reactions.
- Current mechanophores often have limited reactivity pathways due to two-point force loading.
- Diverse mechanically induced outcomes are restricted by single-pathway reactivity.
Purpose of the Study:
- To develop a novel mechanophore capable of activating multiple reaction pathways simultaneously.
- To explore the use of multi-arm force loading for enhanced mechanochemical control.
- To expand the scope of force-responsive molecular design.
Main Methods:
- Design and synthesis of a fluorinated 1,2-diazetidinone-based mechanophore.
- Application of three-arm pulling geometry for force application.
- 19F NMR spectroscopy for identification and quantification of reaction products.
- Computational analysis to understand reaction pathway selectivity.
Main Results:
- The mechanophore simultaneously activated two orthogonal reaction pathways under three-arm pulling.
- Parallel scission reactions generated imine/isocyanate and azo/ketene products.
- 19F NMR spectroscopy enabled unambiguous identification of mechanically generated species.
- Computational analysis confirmed favored N1-N2 bond cleavage and suppressed pathway interconversion.
Conclusions:
- Multi-arm force loading is a viable strategy for accessing multiple, independent mechanochemical transformations.
- This approach significantly expands the conceptual and practical scope of mechanophore design.
- The developed mechanophore offers enhanced control over force-induced chemical reactivity.
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