Collect. Czech. Chem. Commun. 2001, 66, 1638-1658

Construction of Interconnected Acidity Functions Based on ortho Substituted Anilines and N-Methylanilines as Indicators

Oldřich Pytelaa,*, Jiří Kulháneka, Eva Jiráskováb and Taťjana Nevěčnáb

a Department of Organic Chemistry, University of Pardubice, 532 10 Pardubice, Czech Republic
b Department of Inorganic and Physical Chemistry, Palacký University Olomouc, 771 46 Olomouc, Czech Republic


The log I values of 15 mainly ortho substituted derivatives of aniline and N-methylaniline have been measured spectrophotometrically in sulfuric, perchloric, and methanesulfonic acids. A new algorithm has been suggested for construction of acidity functions enabling simultaneous and independent construction of acidity functions in various media under the condition of equal values of pKa of the same indicators in the given media. The so-called interconnected acidity functions have been constructed with using this algorithm and the log I values measured in the above media, and the pKa values have been calculated. The resulting acidity functions and pKa values agree well with the corresponding literature data.

Keywords: Acidity functions; Basicity; Amines; Anilines; N-Methylanilines; ortho-Effect; Substituent effects.

References: 43 live references.