Aminohydroxypropane Esters of Hydroxyethylidenebisphosphonic Acid

Abstract

The 1-hydroxyethylidene-1,1-bisphosphonic acid (HEDP) (I) reacts with epichlorohydrine (II) and aminoepoxypropanes (III) in water. Optimum pH for the esterefication is 6–7. The reaction completes in 20–30 h on 60°C at this pH and leads to the mixture of the original HEDP with the mono- and diesters. The mixture of di-Na salts of HEDP and the monochloroester (IV) in ratio 1:1.7 was precipitated from the reaction solution on using of the epichlorohydrine (II). This mixture was used for synthesis of aminoesters (VI a,b) unavailable by direct reaction of HEDP with corresponding aminoepoxides.