Synthesis of Optically Active 5-Substituted-2-pyrrolidinone Derivatives Having Atropisomeric Structure and 3,5-<i>Cis</i>-Selective Reaction of Their Enolates with Electrophiles
having an atropisomerism-like structure were prepared from ortho-substituted aniline derivatives and (S)-5-(methoxymethyl)butyrolactone in a stereoselective manner. The reactions of Li-enolates from these lactams with various electrophiles and subsequent dearylation of the products gave 3, 5-cis-disubstituted-2-pyrrolidinone derivatives.