Computational study of carbon–hydrogen bond deprotonation by alkali metal superbases

Deprotonation of hydrocarbon C–H bonds by alkali metal amide “superbases” is analyzed with the use of density functional theory calculations. The role of alkali metal, amide substituents (NH2 versus NH(cyclohexyl)), solvent (implicit and explicit), and substrate (methane versus toluene) are probed. Additionally, Hammett and energy decomposition analyses are utilized to assess the nature of the charge distribution in these transition states. Implications of the present study for the cleavage of strong C–H bonds found in natural gas, such as methane and ethane, are discussed.