The ground state destabilization theory proposes that the electron-electron repulsion between the alpha lone-pair and nucleophilic electron pair destabilize each other by electronic repulsion (filled–filled orbital interaction) thereby decreasing the activation barrier by increasing the ground state energy and making it more reactive. This explains the higher reactivity of α-nucleophiles, however, this electronic mechanism should also increase the basicity and, therefore, cannot fully explain the α-effect.