Asymmetric Conjugate Addition to α-Substituted Enones/Enolate Trapping

Nicolas Germain (1, 2) , Laure Guénée (3) , Marc Mauduit (4) , Alexandre Alexakis (5)

1 Endocrinologie, Diabète et Maladies Métaboliques
2 LIBM - Laboratoire Interuniversitaire de Biologie de la Motricité
3 Département de chimie physique [Genève]
4 ISCR - Institut des Sciences Chimiques de Rennes
5 LPS - Laboratoire de Physique Statistique de l'ENS

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.

Domains: Chemical Sciences; Catalysis

Nicolas Germain, Laure Guénée, Marc Mauduit, Alexandre Alexakis. Asymmetric Conjugate Addition to α-Substituted Enones/Enolate Trapping. Letters in Organic Chemistry, 2014, 16 (1), pp.118-121. ⟨10.1021/ol403104s⟩. ⟨hal-01123659⟩