Related Experiment Video
Updated: Feb 21, 2026
Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
Comparison Between Solid Catalysis and Electrochemical Catalysis in the Synthesis of Methyl Carbamate via Hofmann
Seba Nassif1, Rasha Alabbas1, Ahmade Alassaf1
1Department of Chemistry, Faculty of Sciences, Al Baath University, Homs, Syria.
Introduction:
Hofmann rearrangement reactions are important organic reactions used to obtain carbamates, which are formed via isocyanate as an intermediate compound. Since carbamates have applications in various fields, such as pharmaceuticals, agricultural chemistry, and herbicides, this research focuses on synthesizing carbamates using environmentally friendly methods like solid catalysts and electrical techniques due to their unique characteristics in enhancing selectivity and minimizing solvents. Additionally, a comparison between the two methods was made.
Materials And Methods:
In this study, two methods were employed to obtain carbamate. The first method utilized heterogeneous catalysis with sodium halide-modified aluminum oxide to achieve a high basic surface area alongside sodium hypochlorite as a safe and inexpensive oxidant. The second method employs electrochemical catalysis using a carbon anode and a zinc cathode, with sodium halides serving as intermediates.
Results:
Sodium chloride modified with aluminum oxide demonstrated better results than sodium bromide and iodide. A higher yield of carbamates was obtained in a shorter time and at moderate temperatures. In contrast, in the electrochemical method, sodium bromide demonstrated the best performance, achieving 75% conversion under ambient conditions.
Conclusion:
The comparison between the two methods revealed that the electrochemical method significantly outperformed, as it managed to avoid side products and directed the reaction towards the target compound under mild conditions. Whereas the solid catalytic method (Al2O3/NaCl) obtained lower yields and produced side products in a shorter reaction time.
More Related Videos
Related Concept Videos
02:50Catalysis
02:34Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
02:36Regioselectivity and Stereochemistry of Hydroboration
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
01:28Multiple Halogenation of Methyl Ketones: Haloform Reaction
01:17Thermal Electrocyclic Reactions: Stereochemistry
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
02:17Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...