Die Dissoziationskonstanten von 2,3′-und 2,4′-Dihydroxydiphenylmethanderivaten

The pK-values of the first and second degree of dissociation of 2.3-dihydroxy-6-methyl-3.5-dinitro-diphenylmethane, 2.3-dihydroxy-6-methyl-5-nitro-diphenylmethane, 2.3-dihydroxy-5.6-dimethyl-3-nitro-diphenylmethane, 2.4-dihydroxy-3. 5-dimethyl-3.5-dinitro-diphenylmethane, 2.4-dihydroxy-3. 5-dimethyl-5-nitro-diphenylmethane and 2.4-dihydroxy-3.5.5-trimethyl-3-nitrodiphenylmethane were determined in aqueous solution at 25°C by the spectrophotometric method. The observed pK-values are compared with those of 2-methyl-4.6-dinitro-phenol, 2-methyl-4-nitrophenol, 2.4-dimethyl-6-nitrophenol, 3.4-dimethylphenol and 2.4.6-trimethylphenol which serve as model compounds for the single phenolic units.