Carbocations as Lewis Acid Catalysts: Reactivity and Scope
نویسندگان
چکیده
One potential Lewis acid that has received negligible attention as a catalyst is the carbocation. Here we show the potential of triaryl methylium ions as highly powerful Lewis acid catalysts for organic reactions. The Lewis acidity of the triaryl methylium ion can be easily tuned by variation of the electronic properties of the aromatic rings and the catalytic activity of the carbocation is shown to correlate directly to the level of stabilization of the empty pC-orbital at the cationic carbon. The versatility of triaryl methylium ions as efficient Lewis acid catalysts for organic reactions is demonstrated in Diels-Alder, aza-DielsAlder, conjugate addition, halogenation, epoxide rearrangement and intra molecular hetro-ene reactions.
منابع مشابه
Carbocations as Lewis acid catalysts in Diels-Alder and Michael addition reactions.
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