Dissociation constants and infrared spectra of boron trifluoride complexes of substituted benzamides

Abstract

The logarithms of the dissociation constants, like the pK_a′s of benzamide conjugate acids, are correlated better by σ than by σ⁺ substituent parameters. This result is discussed in the light of infrared spectral work and Hückel molecular orbital calculations, and in comparison with the pK_a′s of protonated benzoic acids.