Subscribe to RSS
Please copy the URL and add it into your RSS Feed Reader.
https://www.thieme-connect.de/rss/thieme/en/10.1055-s-00000131.xml
Synfacts 2009(2): 0178-0178
DOI: 10.1055/s-0028-1087630
DOI: 10.1055/s-0028-1087630
Metal-Catalyzed Asymmetric Synthesis and Stereoselective Reactions
© Georg Thieme Verlag
Stuttgart ˙ New York
Lewis Base Assisted Brønsted Base: Phosphine Oxides and La-Aryloxides
H. Morimoto, T. Yoshino, T. Yukawa, G. Lu, S. Matsunaga*, M. Shibasaki*
The University of Tokyo, Japan
Further Information
Publication History
Publication Date:
22 January 2009 (online)
Significance
Combined acid and base catalysis is a well-established concept which has led to the development of highly reactive systems. However, utilization of a Lewis base to activate a Brønsted base in a catalytic system is genuinely rare. The authors report that addition of a bidentate phosphine oxide Lewis base to a lanthanum aryl oxide produces a highly reactive catalyst for the anti-selective Mannich-type reaction. In control experiments, with the absence of Lewis base, La(OAr)3 gives both poor reactivity and diastereoselectivity.