Non-Chelate-Controlled Addition of 1-Bromo-1-lithio-1-alkenes to O-Protected Lactaldehydes

Authors

  • Prof. Dr. Manfred Braun,

    Corresponding author
    1. Institut für Organische und Makromolekulare Chemie der Unniversität, Universitätsstrasse 1, D-4000 Düsseldorf 1 (FRG)
    • Institut für Organische und Makromolekulare Chemie der Unniversität, Universitätsstrasse 1, D-4000 Düsseldorf 1 (FRG)
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  • Dipl.-Chem. Hellmut Mahler

    1. Institut für Organische und Makromolekulare Chemie der Unniversität, Universitätsstrasse 1, D-4000 Düsseldorf 1 (FRG)
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  • This work was supported by the Deutsche Foreschungsgemeinschaft, the Fonds der Chemischen Industrie, and BASF AG (donation of chemicals).

  • In memoriam Hans Musso

Abstract

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Non-chelate control is generally difficult to realize. With the carbenoid 2 it has now been possible for the first time to carry out such an addition (85 % de) of an organolithium compound to the protected lactaldehyde (S)-1. A chiral 1 bromo-l-lithio-l-alkene increases the diastereoselectivity to 95 % de. The product 4 separated the formal after dehalogenation and ozonolysis is formed by the formal addition of ⊖CH2OH.

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