329. N. Germain, L. Guénée, M. Mauduit, A. Alexakis,
     “Asymmetric Conjugate Addition to α-Substituted Enones/Enolate Trapping”
     Org. Lett. 2014, 16, 118-121.

An NHC–Cu complex catalyzed the asymmetric conjugate addition (ACA) of various Grignard reagents to nonactivated α-substituted cyclic enones to give 2,3-dialkylated cyclopentanones and cyclohexanones. The Michael addition features the formation of a magnesium enolate intermediate. One-pot diastereoselective trapping of this enolate by alkyl, propargyl, allyl, and benzyl halides led to ketones with contiguous α-quaternary and β-tertiary centers.

DOI : 10.1021/ol403104s 

archive ouverte unige:32843