α-Hydroxyphosphonates as versatile starting materials

Abstract

α-Hydroxyphosphonates constitute a class of organophosphorus compounds famous for their bioactive properties. α-Hydroxyphosphonates may easily be functionalized due to their free hydroxy function in the α position resulting in new families of compounds of synthetical and biological interest. This review paper summarizes the main reaction types of α-hydroxyphosphonates. First, the syntheses of α-aminophosphonates and α-hydroxyphosphonic acids are discussed, as from a biological point of view, these are the most important classes of compounds derived from α-hydroxyphosphonates. After that, the O-acylation and O-alkylation of α-hydroxyphosphonates to afford O-acyloxy and O-alkoxyphosphonates are presented. The discussion continues with the synthesis of α-halophosphonates and α-ketophosphonates that are valuable synthetic intermediates. After that, a few examples for the reduction of α-hydroxyphosphonates are presented, followed by the rearrangement of α-hydroxyphosphonates to the corresponding benzyl phosphates. Beside the interesting examples from the literature, the main synthetic results of our research group in this field are also discussed.

Graphical Abstract

Keywords:

• α-hydroxyphosphonates
• α-aminophosphonates
• α-ketophosphonates
• green syntheses
• phosphorylation
• phospha-Brook rearrangement