α-Deprotonation of an α-Chiral 2-Alkenylcarbamate with Retention and Lithium-Titanium Exchange with Inversion— the Homoaldol Reaction with 1,3-Chirality Transfer

Authors

  • Prof. Dr. Dieter Hoppe,

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    1. Institut für Organische Chemie der Universität, Olshausenstrasse 40, D-2300 Kiel 1 (FRG)
    • Institut für Organische Chemie der Universität, Olshausenstrasse 40, D-2300 Kiel 1 (FRG)
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  • Thomas Krämer

    1. Institut für Organische Chemie der Universität, Tammannstrasse 2, D-3400 Göttingen (FRG)
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  • Metalated Nitrogen Derivatives of Carbon Dioxide in Organic Synthesis, Part 31. This work was supported by the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen Industrie.—Part 30: D. Hoppe, C. Gonschorrek, E. Egert, D. Schmidt, Angew. Chem. 97 (1985) 706; Angew. Chem. Int. Ed. Engl. 24 (1985) 700.

  • Dedicated to Professor Hans Musso on the occasion of his 60th birthday

Abstract

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One approach to asymmetric homoaldol reactions may be provided by the surprising finding that the lithium compound 1 racemizes only very slowly at − 78°C. Compound 1 reacts with ClTi(Net2)3 with inversion to give a species that can add to carbonyl compounds with 1,3-chirality transfer.

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