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Friedel-Crafts Type Methylation with Dimethylhalonium Salts
Sebastian Hämmerling1, Patrick Voßnacker1, Simon Steinhauer1
1Institut für Chemie und Biochemie, Freie Universität Berlin, Fabeckstr.34/36, 14195, Berlin, Germany.
The dimethylchloronium salt effectively methylates electron-deficient aromatic systems in Friedel-Crafts reactions. Quantum-chemical calculations explored the cation
Area of Science:
- Organic Chemistry
- Computational Chemistry
Background:
- Friedel-Crafts reactions are fundamental in organic synthesis.
- Methylation of electron-deficient aromatic systems presents challenges.
Purpose of the Study:
- To investigate the methylation of electron-deficient aromatic systems using a novel dimethylchloronium salt.
- To elucidate the role of the dimethylchloronium cation in Friedel-Crafts type reactions through computational analysis.
Main Methods:
- Synthesis of N-methylated cations using [Me2Cl][Al(OTeF5)4].
- Quantum-chemical calculations to study the reaction mechanism and cation behavior.
Main Results:
- Successful synthesis of N-methylated cations like [MeNC5F5]+, [MeNC5F4I]+, and [MeN3C3F3]+.
- Computational analysis provided insights into the dimethylchloronium cation's role in the methylation process.
Conclusions:
- The dimethylchloronium salt is a potent reagent for methylating challenging aromatic substrates.
- Understanding the cation's behavior is key to optimizing Friedel-Crafts methylation strategies.
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