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

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.