Superbases in the gas phase: Amidine and guanidine derivatives with proton affinities larger than 1000 kj mol ⁻¹

Abstract

Abstract By building a relative basicity ladder, the current basicity scale (Lias et al., J. Phys. Chem. Ref. Data , 17 Suppl. No. 1 (1988)) has been reexamined in its upper part, and extended for organic compounds (amenable to proton transfer measurements) up to proton affinity, PA = 1050 kJ mol −1 . Structural effects involved in superbasicities are briefly discussed and routes to further extension of the gas‐phase basicity scale for organic compounds are proposed.