Efficient Access to Trifluoromethyl Diarylpyrrolines and their N-Oxides through Enantioselective Conjugate Addition of Nitromethane to β,β-Disubstituted Enones
The cupreidinium salt 1 catalyzes the highlyenantioselectiveconjugateaddition of nitromethane to β‐aryl‐β‐trifluoromethyl aryl enones (2). The biologically important chiral pyrrolines 4 and N‐oxide 5, having a trifluoromethylated all‐carbon quaternary chiral center, were easily synthesized from the key intermediate (R)‐3 in high to excellent yields. M.S.=molecular sieves.