Asymmetric aldol and alkylation reactions mediated by the 'quat' chiral auxiliary (R)-(−)-5-methyl-3,3-dimethyl-2-pyrrolidinone

Enolates derived from the N -propionoyl derivative of the “quat” chiral auxiliary ( R )-(−)-5-methyl-3,3-dimethyl-2-pyrrolidinone undergo highly stereoselective aldol and alkylation reactions. Removal of the auxiliary has been demonstrated with LiOH, PhCH 2 OLi, MeOMgBr and LiAlH 4 to generate respectively (2 R ,3 R )-3-hydroxy-2-methyl-3-phenylpropionic acid in homochiral form, and with 96% e.e. ( S )-2-methyl-3-phenylpropionic acid and derived methyl and benzyl esters and with >94% e.e. ( S )-2-methyl-3-phenylpropanol.