Theoretical evidence in support of the Anh–Eisenstein electronic model in controlling π-facial stereoselectivity in nucleophilic additions to carbonyl compounds

Abstract
Ab initio MO calculations on the complete set of diastereoisomeric transition structures for the addition of cyanide anion to propanal, fluoroethanal, and 2-fluoropropanal, revealed that the most stable transition structure has the C–F bond in the antiperiplanar position with respect to the forming carbon-nucleophile bond; this finding is consistent with the Anh–Eisenstein model for nucleophilic attack on chiral acyclic carbonyl compounds but not with the Cieplak model.