Synthesis and acid-base properties of aminophosphine oxides on the basis of natural amino acids

Abstract

In recent years aminophosphonate derivatives of the natural amino acids attracted a considerable interest because of their pronounced physiological activity and specific complexing properties [1, 2]. However, the phosphine oxide derivatives of amino acids, which can show high efficiency in liquid and membrane extraction processes [3], were not described up to day. Using the Kabachnik–Fields reaction [1] in a dioctylphosphine–formaldehyde–amino acid threecomponent system, we synthesized a series of αaminomethylphosphine oxides containing structural fragments of glycine (I), β-alanine (II), and its N-butyl derivative (III) of the general formula Oct2P(O)· CH2NR(CH2)nC(O)OH, R = Oct2P(O)CH2, n = 1 (I); R = Oct2P(O)CH2, n = 2 (II); R = C4H9, n = 2 (III).