Crossed-Conjugate Additions of Nitroalkenes and α,β-Unsaturated Aldehydes

Significance

The authors present an enantio­selective intermolecular crossed-conjugate addition of nitroalkenes and α,β-unsaturated aldehydes through a dual Lewis base (LB) activation strategy. In the presence of 20 mol% of the prolinol catalyst, the crossed-conjugate addition proceeded smoothly with the addition of (OMe)₃P and AcOH, providing the adducts in good yields and high enantioselectivities. A synthetic application was demonstrated by the authors, in which the crossed-conjugate addition product 4 was transformed into the only trans-­isomer of substituted pyrrolidine 5.