The vertical electron detachment energies (VDE) of several NaL2- and MgL3- anions (where L = -NO2 -CF3, -CCl3, -SHO3, -COOH, -COOCH3, -CHO, -CONH2) were calculated at the outer valence Green function level with the 6-311++G(3df,3pd) basis sets. It was proposed that some of electrophilic substituents may act as ligands in these species, analogously to halogen atoms in superhalogen anions. The largest values of the electron binding energies were found for the anions containing -SHO3 ligands (VDE = 6.0-8.2 eV) and -CF3 groups (VDE = 5.2-6.6 eV).