Synfacts 2011(6): 0627-0627  
DOI: 10.1055/s-0030-1260431
Metal-Catalyzed Asymmetric Synthesis and Stereoselective Reactions
© Georg Thieme Verlag Stuttgart ˙ New York

Ruthenium-Catalyzed Asymmetric [2+2] Cycloaddition of Ynamides with Enones

Contributor(s):Hisashi Yamamoto, Patrick Brady
C. Schotes, A. Mezzetti*
ETH Zürich, Switzerland
Enantioselective Ficini Reaction: Ruthenium/PNNP-Catalyzed [2+2] Cycloaddition of Ynamides with Cyclic Enones
Angew. Chem. Int. Ed.  2011,  50:  3072-3074  
Further Information

Publication History

Publication Date:
19 May 2011 (online)


Significance

The chiral dicationic ruthenium complex catalyzes the asymmetric [2+2] cyclo­addition of cyclic β-keto esters with ynamides. The reaction tolerates a wide range of substrates and generates an all-carbon quaternary stereogenic center in high yield and with high asymmetric induction.

Comment

Ynamides bearing an electron-deficient and an electron-donating group were found to be ideal substrates for this reaction due to the absence of an uncatalyzed background reaction at elevated temperatures.