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Direct B-H Bond Activation Polymerization of Boron Clusters
Meng Chen1,2, Zhaofeng Sun1, Liyan Wang1
1State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Journal of the American Chemical Society
|November 11, 2025
Summary
Researchers developed a new Pd-catalyzed polymerization of carboranes, creating high-molecular-weight polymers. These novel boron cluster polymers are degradable and show promise for bioimaging and neutron capture therapy.
Area of Science:
- Polymer Chemistry
- Materials Science
- Boron Cluster Chemistry
Background:
- Functionalizing boron clusters like carboranes at boron vertices is synthetically challenging due to inert B-H bonds and regioselectivity.
- While B-H bond functionalization is advancing for small molecules, boron cluster-based polymer synthesis via direct B-H activation polymerization is unexplored.
Purpose of the Study:
- To develop a novel polymerization method for constructing boron cluster-based polymers.
- To explore the synthesis of degradable, multifunctional polymers using carboranes and diynes.
Main Methods:
- Palladium-catalyzed B-H bond activation polymerization of nido-carboranes with internal diynes.
- Characterization of resulting polymers for molecular weight, yield, and degradability.
Main Results:
- Achieved high molecular weights (up to 103.8 kg/mol) and excellent yields (up to 99%) in boron-site-substituted polymers.
- Demonstrated excellent degradability of the polymers due to dense nido-carborane incorporation.
- Synthesized aggregation-induced emission (AIE)-active polymers for bioimaging and boron delivery agents.
Conclusions:
- Established a general and facile route to degradable, multifunctional boron cluster-based polymers.
- Showcased the potential of these polymers in materials science and biomedicine, including bioimaging and neutron capture therapy.
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