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Superacid-catalyzed reactions of olefinic pyrazines: an example of anti-Markovnikov addition involving superelectrophiles.

ABSTRACT: [reaction: see text] Olefinic pyrazines are found to react with benzene in CF3SO3H and give anti-Markovnikov-type addition products. We propose that this is caused by two effects: destabilization of the carbocationic intermediates that would lead to Markovnikov-type products and the generation of a considerable amount of positive charge at the terminal carbon of the olefinic groups. This suggests that acid-catalyzed addition reactions can give anti-Markovnikov-type products when a multiply charged (i.e., superelectrophilic) group is adjacent to the olefinic site.

SUBMITTER: Zhang Y

PROVIDER: S-EPMC2883295 | biostudies-literature | 2005 Jun

REPOSITORIES: biostudies-literature

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Superacid-catalyzed reactions of olefinic pyrazines: an example of anti-Markovnikov addition involving superelectrophiles.

Zhang Yiliang Y Briski Jason J Zhang Yun Y Rendy Rendy R Klumpp Douglas A DA

Organic letters 20050601 12

[reaction: see text] Olefinic pyrazines are found to react with benzene in CF3SO3H and give anti-Markovnikov-type addition products. We propose that this is caused by two effects: destabilization of the carbocationic intermediates that would lead to Markovnikov-type products and the generation of a considerable amount of positive charge at the terminal carbon of the olefinic groups. This suggests that acid-catalyzed addition reactions can give anti-Markovnikov-type products when a multiply charg ...[more]

PMID: 15932234

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