Molecules, Vol. 23, Pages 1493: Synthesis and Reactions of α-Hydroxyphosphonates
Molecules doi: 10.3390/molecules23061493
This review summarizes the main synthetic routes towards &alpha;-hydroxyphosphonates that are known as enzyme inhibitors, herbicides and antioxidants, moreover, a number of representatives express antibacterial or antifungal effect. Special attention is devoted to green chemical aspects. &alpha;-Hydroxyphosphonates are also versatile intermediates for other valuable derivatives. O-Alkylation and O-acylation are typical reactions to afford &alpha;-alkoxy-, or &alpha;-acyloxyphosphonates, respectively. The oxidation of hydroxyphosphonates leads to ketophosphonates. The hydroxy function at the &alpha; carbon atom of hydroxyphosphonates may be replaced by a halogen atom. &alpha;-Aminophosphonates formed in the nucleophilic substitution reaction of &alpha;-hydroxyphosphonates with primary or secondary amines are also potentially bioactive compounds. Another typical reaction is the base-catalyzed rearrangement of &alpha;-hydroxy-phosphonates to phosphates. Hydrolysis of the ester function of hydroxyphosphonates leads to the corresponding phosphonic acids.