Protolytic and complexing properties of 2-alkylaminomethylphenols with respect to copper(II) in aqueous ethanol

Abstract

The acid-base and complexing properties of 2-butyl- (HL1), octyl- (HL2), dibutyl- (HL3), and dipentylaminophenol (HL4) in aqueous ethanol were characterized by spectrophotometry, pH measurements, and mathematic modeling of equilibria in solutions [T = 25 ± 0.05°C, μ = 0.1 (KNO3)]. The factors increasing and reducing the basicity of the amino group and the acidity of the phenol group were shown to compete in the ligands studied. Mono- and dialkylaminomethylphenols containing the same donor atoms form the mononuclear [CuL]+ and [CuL2] complexes and the dinuclear [Cu2(HL1)4]4+ and [Cu2(HL)3L]3+ complexes with the copper(II) cations.