Water as a promoting media for 1,3-dipolar cycloaddition of phosphorylated azides to internal alkynes

Abstract

The 1,3-cycloaddition of -phosphoryl azides to activated internal alkynes such as dimethyl acetylenedicarboxylate and tetramethyl acetylenediphosphonate as well sodium azide to tetramethyl acetylenediphosphonate readily proceeds in water without any co-solvent or additive to afford the corresponding phosphorylated 1,2,3-triazoles in excellent yields. The ester group in carbalkoxy function of these compounds can be easily converted to carbamido group via the reaction with amines in MeOH thereby expanding the range of potentially biologically active heterocyclic aminophosphonates of such type.