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A Very Strong Methylation Agent: [Me2 Cl][Al(OTeF5 )4 ]
Sebastian Hämmerling1, Günther Thiele1, Simon Steinhauer1
1Freie Universität Berlin, Institut für Chemie und Biochemie, Fabeckstr.34/36, 14195, Berlin, Germany.
Angewandte Chemie (International Ed. in English)
|May 4, 2019
Summary
Researchers developed a new chloronium salt, [Me2Cl][Al(OTeF5)4], for efficient electrophilic methylation. This stable compound effectively methylates weak bases, showcasing its utility in synthetic chemistry.
Area of Science:
- Inorganic Chemistry
- Organometallic Chemistry
- Synthetic Chemistry
Background:
- Chloronium salts are reactive intermediates.
- Electrophilic methylation is a key synthetic transformation.
- Development of stable, easy-to-handle methylation agents is ongoing.
Purpose of the Study:
- To synthesize a novel chloronium-containing salt.
- To evaluate its stability and handling properties.
- To demonstrate its efficacy as an electrophilic methylation agent.
Main Methods:
- A simple one-pot synthesis procedure.
- Multigram scale preparation of the salt.
- Reactions with weak bases like P(CF3)3, PF3, MeI, and MeBr.
Main Results:
- Successful synthesis of [Me2Cl][Al(OTeF5)4] on a multigram scale.
- The salt is isolable and can be handled at room temperature.
- Effective methylation of very weak bases was achieved.
Conclusions:
- The new chloronium salt is a stable and potent electrophilic methylation agent.
- Its ease of handling and synthesis makes it a valuable tool for organic synthesis.
- Demonstrated utility in methylating challenging substrates like PF3 and P(CF3)3.
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