Chiral Acetals as Stereoinductors: Diastereoface Selective Alkylation of Dihydrobenzoxazine-Derived Amide Enolates

J. Org. Chem., 65 (20), 6540 -6546, 2000. 10.1021/jo000352o S0022-3263(00)00352-2
Web Release Date: September 13, 2000

Chiral Acetals as Stereoinductors: Diastereoface Selective Alkylation of Dihydrobenzoxazine-Derived Amide Enolates

Johann Mulzer* and Oliver Langer

Institut für Organische Chemie der Universität Wien, Währingerstr. 38, A-1090 Wien, Austria

Martin Hiersemann*

Institut für Organische Chemie der Technischen Universität Dresden, D-01062 Dresden, Germany

Jan W. Bats

Institut für Organische Chemie der Johann Wolfgang Goethe-Universität, Marie-Curie-Strasse 11, D-60439 Frankfurt, Germany

Jürgen Buschmann and Peter Luger

Institut für Kristallographie der Freien Universität, Takustrasse 6, D-14195 Berlin, Germany

mulzer@felix.orc.univie.ac.at

Received March 13, 2000

Abstract:

Novel dihydrobenzoxazine-derived acetals of type 3 have been developed for asymmetric C-alkylations of propionyl amide enolates. High stereoselectivities are obtained for amides 15 and 22 which are rationalized in terms of intramolecular metal chelate formation.