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Experimental and Theoretical Study of Cyclic Amine Catalysed Urethane Formation
Hadeer Q Waleed1,2, Dániel Pecsmány1,2, Marcell Csécsi1
1Institute of Chemistry, University of Miskolc, 3515 Miskolc-Egyetemváros, Hungary.
Polymers
|July 27, 2022
Summary
Cyclic amine catalysts significantly lower the energy barrier for urethane synthesis from phenyl isocyanate and butanol. This study combines kinetic and computational methods to understand urethane formation, paving the way for new catalyst designs.
Area of Science:
- Organic Chemistry
- Catalysis
- Computational Chemistry
Background:
- Urethane synthesis is crucial in polymer and materials science.
- Amine catalysts are known to influence reaction rates.
- Understanding the mechanism of alcoholysis of isocyanates is key for process optimization.
Purpose of the Study:
- To investigate the role of cyclic amine catalysts in the alcoholysis of phenyl isocyanate.
- To elucidate the molecular mechanism of urethane formation using computational methods.
- To compare computed thermodynamic properties with experimental data.
Main Methods:
- Combined kinetic and mechanistic study.
- G3MP2BHandHLYP composite method for molecular mechanism.
- SMD implicit solvent model.
- Thermodynamic property analysis.
Main Results:
- Cyclic amine catalysts significantly reduce the activation energy for urethane formation.
- Computed and measured thermodynamic properties show good agreement.
- The presence of catalysts enhances the reaction energetics.
Conclusions:
- Amine catalysts play a vital role in urethane synthesis.
- The computational approach provides accurate mechanistic insights.
- This research facilitates the future design of novel catalysts for urethane production.
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