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Preparation of an enantioenriched product from achiral or racemic starting materials, such that one enantiomer predominates, is enantioselective synthesis. The stereochemical bias may come from a chiral catalyst, a chiral reagent, or a chiral auxiliary that is later removed; the defining outcome is unequal formation of the two mirror-image products. Catalytic enantioselective construction of quaternary carbon stereocenters is a stringent instance in which the new stereogenic carbon bears four non-hydrogen substituents ^[1]. Related methods create all-carbon quaternary stereogenic centers in acyclic frameworks, where conformational flexibility makes facial discrimination more demanding ^[2]. Phase-transfer catalysis of alkylation of achiral Schiff-base glycine esters produces enantioenriched α-amino acids and exemplifies reagent- or catalyst-controlled enantioselective C–C bond formation at a prochiral enolate ^[3]. The concept names the synthetic objective and its stereochemical result, whereas enantioselective catalysis names the catalytic means. Resolution of a racemate is not enantioselective synthesis of that racemate’s constituents, because the stereocenters already exist before separation.