Catalytic Enantioselective Conjugate Addition of Nitromethane to α′‐Hydroxy Enones as Surrogates of α,β‐Unsaturated Carboxylic Acids and Aldehydes

No base is required for the Mg(II)‐catalyzed conjugate addition of nitromethane to α′‐hydroxy enones in the presence of molecular sieves. Good enantioselectivities are attained using 3 or 4 Å MS and about 10 mol % of Mg(OTf)2‐chiral bisoxazoline complexes. Elaboration of the adducts through oxidative cleavage of the ketol moiety provides an entry to enantioenriched γ‐nitro carboxylic acids, while a sequential carbonyl reduction‐diol oxidation yields the corresponding aldehydes.