Spectroscopic Studies on Molecular Interactions. V. Charge-Transfer Property and Enzymatic Acetylation of Aniline Derivatives

Abstract

The first ionization potential, I_P, of 10 aniline derivatives was estimated from the charge-transfer absorption spectra arizing in the 510-560 mμ region due to their interactions with p-chloranil. The relation of I_p to the rate of enzymatic acetylation, V_Ac, indicated that V_Ac, and possibly affinity to the enzyme, increased with an increase in charge-transfer ability of the anilines. But it was also found that V_Ac became greater with an increase in basicity of the anilines ; this was compatible with the theory for the usual organic acylation. Accordingly, whether or not the charge-transfer was actually concerned with the enzymatic reaction could not be determined from this study, except from the standpoint that organic ionic reactions were generally involved in the transfer of charge. The relation of I_P to pK_a was theoretically discussed.