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

The acid-base and complexing properties of 2-butyl- (HL1), octyl- (HL2), di butyl- (HL3), and dipentylaminophenol (HL4) in aqueous ethanol were charact erized by spectrophotometry, pH measurements, and mathematic modeling of eq uilibria in solutions [T = 25 +/- 0.05 degrees C, mu = 0.1 (KNO3)]. The fac tors increasing and reducing the basicity of the amino group and the acidit y of the phenol group were shown to compete in the ligands studied. Mono- a nd dialkylaminomethylphenols containing the same donor atoms form the monon uclear [CuL](+) and [CuL2] complexes and the dinuclear [Cu-2(HL1)(4)](4+) a nd [Cu-2(HL)(3)L](3+) complexes with the copper(II) cations.