(o‐Hydroxyphenyl)methylphosphonic acids: Synthesis and potentiometric determinations of their pKa Values

Abstract ( o ‐Hydroxyphenyl)methylphosphonic acids are readily obtained from o ‐(bromomethyl)‐ or o ‐(hydroxymethyl)phenols and trialkyl phosphites. Subsequent hydrolysis leads to the corresponding phosphonic acids. For a series of such compounds, the p K a values have been determined by potentiometry. Their dependence on additional substituents in the aromatic ring is discussed in terms of electronic and steric effects.