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Updated: Sep 23, 2025
12:19
Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
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A Water-Compatible NHC-Borane: Photopolymerizations in Water and Rate Constants for Elementary Radical Reactions
Mohamad-Ali Tehfe1, Julien Monot2,3, Max Malacria2
1Institut de Science des Matériaux de Mulhouse IS2M, LRC CNRS 7228, ENSCMu-UHA; 15, rue Jean Starcky, 68057 Mulhouse Cedex, France.
ACS Macro Letters
|May 17, 2022
Summary
2,4-dimethyl-1,2,4-triazol-3-ylidene borane (1) and its boryl radical show stable reaction rates in water. This borane (1) is an effective co-initiator for visible light photopolymerization under air and water.
Area of Science:
- Organic Chemistry
- Polymer Chemistry
- Photochemistry
Background:
- Boranes are versatile compounds with applications in catalysis and synthesis.
- Ylidene boranes represent a specific class of organoboron compounds.
- Understanding their reactivity in the presence of water is crucial for practical applications.
Purpose of the Study:
- To measure the rate constants of elementary reactions involving 2,4-dimethyl-1,2,4-triazol-3-ylidene borane (1) and its derived boryl radical.
- To investigate the influence of water on these reaction rates.
- To evaluate the potential of borane (1) as a co-initiator in photopolymerization.
Main Methods:
- Kinetic studies measuring rate constants for H-abstraction, radical addition, halogen abstraction, and oxidation.
- Comparative analysis of reaction rates in the presence and absence of 1.5 M water.
- Assessment of borane (1) as a co-initiator in visible light photopolymerization.
Main Results:
- Key elementary reactions of borane (1) and its radical are unaffected by high concentrations of water.
- Reactions studied include H-abstraction, addition to methyl acrylate, halogen abstraction, and oxidation.
- Borane (1) demonstrates efficiency as a co-initiator for photopolymerization under ambient air and water conditions.
Conclusions:
- The stability of 2,4-dimethyl-1,2,4-triazol-3-ylidene borane (1) and its radical in aqueous environments is confirmed.
- Borane (1) is a robust and effective co-initiator for visible light photopolymerization, even in the presence of air and water.
- These findings support the use of borane (1) in diverse polymerization applications.
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