THE FORMATION OF α-AMINO AND α-HYDROXY-ALKANEPHOSPHONIC ACIDS IN THE REACTIONS OF PHOSPHITE ESTERS WITH ALDEHYDES AND ALKYL CARBAMATES

Abstract

The preparation of α-aminoalkanephosphonic acids from triphenyl phosphite, an aldehyde, and ethyl or benzyl carbamate in glacial acetic acid, followed by hydrolysis, is accompanied by the formation of the corresponding α-hydroxyphosphonic acid. Reaction in toluene, using boron trifluoride-etherate as catalyst, affords an alternative reparative procedure but does not prevent the formation of α-hydroxyphosphonic acid. ³¹P nmr reveals the presence of numerous intermediates. The reactions are discussed.

Key Words:

• Aminophosphonic acids
• hydroxyphosphonic acids
• ³¹P NMR spectroscopy