Nucleophilic substitution at the alkenyl and cyclopropyl carbon atoms of magnesium carbenoids: a DFT study

The results of DFT calculations demonstrated that the activation free energies for the nucleophilic substitution of (1-chlorovinyl)- and (1-chlorocyclopropyl)magnesium chlorides with a chloride ion were lower than those of chloroethene and chlorocyclopropane by 8.1 and 4.4 kcal/mol, respectively, which suggests that the magnesium atom on the electrophilic carbon atom facilitates nucleophilic substitution. The activation energies for the nucleophilic substitution of (1-chlorovinyl)magnesium chloride with methyl anion, vinyl anion, and acetylide ion via the 1,2-migration were calculated to be 21.3–23.2 kcal/mol.