Synthesis of triazolyl-alkylphosphonate starting from ω-azidoalkylphosphonates or ω-alkynylphosphonates

1,2,3-Triazolyl-alkylphosphonates are synthesised according to a Huisgen 1,3-dipolar cycloaddition catalysed by copper salts. The cycloaddition of either an alkynylphosphonate with an azidoalkane or an azido-phosphonate with an alkyne is achieved in high yield and regiospecifically. As an illustration of the functionalisation of aromatic ligands by using the catalytic version of the Huisgen reaction, the coupling of 3-ethynyl-1,10-phenanthroline with azidoalkylphosphonate is reported.