Synthesis, acid‒base properties, and complexing properties of N,N-bis[butoxy(hydroxy)phosphinoylmethyl]glycine

Abstract

N,N-Bis(dibutoxyphosphinoylmethyl)glycine was synthesized by the Kabachnik‒Fields reaction in the three-component system glycine hydrochloride–formaldehyde–dibutyl hydrogen phosphite. Saponification of the product gave N,N-bis[butoxy(hydroxy)phosphinoylmethyl]glycine as the normal potassium salt. pH-Metric titration was used to determine the ionization constants of N,N-bis[butoxy(hydroxy)phosphinoylmethyl]-glycine, аs well as the stability constants of its Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) complexes.