Angewandte Chemie International Edition in English

Volume 28, Issue 9 pp. 1267-1268

Communication

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Isolation of a Zwitterion in a Diels–Alder Reaction with Inverse Electron Demand^†

Dipl.-Chem. Klaus-Peter Hartmann,

Dipl.-Chem. Klaus-Peter Hartmann

Institut für Organische Chemie der Universität, Karlstrasse 23, D-8000 München 2(FRG)

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Priv.-Doz. Dr. Manfred Heuschmann,

Corresponding Author

Priv.-Doz. Dr. Manfred Heuschmann

Institut für Organische Chemie der Universität, Karlstrasse 23, D-8000 München 2(FRG)

Institut für Organische Chemie der Universität, Karlstrasse 23, D-8000 München 2(FRG)Search for more papers by this author

Dipl.-Chem. Klaus-Peter Hartmann,

Dipl.-Chem. Klaus-Peter Hartmann

Institut für Organische Chemie der Universität, Karlstrasse 23, D-8000 München 2(FRG)

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Priv.-Doz. Dr. Manfred Heuschmann,

Corresponding Author

Priv.-Doz. Dr. Manfred Heuschmann

Institut für Organische Chemie der Universität, Karlstrasse 23, D-8000 München 2(FRG)

Institut für Organische Chemie der Universität, Karlstrasse 23, D-8000 München 2(FRG)Search for more papers by this author

First published: September 1989

https://doi.org/10.1002/anie.198912671

Citations: 27

^†

This work was supported by the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen Industrie.

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Graphical Abstract

The Diels–Alder reaction between tetrazine 1 and the ketene-N,N acetal 2 is not concerted but rather a two-step process. At temperatures < −15 °C it proved possible to isolate the zwitterion 3, which reacted further to 4 upon warming. Previously confusing phenomena associated with such reactions now merit reconsideration and systematic investigation.

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Volume28, Issue9

September 1989

Pages 1267-1268

Isolation of a Zwitterion in a Diels–Alder Reaction with Inverse Electron Demand^†

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Isolation of a Zwitterion in a Diels–Alder Reaction with Inverse Electron Demand†

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Isolation of a Zwitterion in a Diels–Alder Reaction with Inverse Electron Demand^†