Room‐Temperature Alkynylation of Phosphine Oxides with Copper Acetylides: Practical Synthesis of Alkynylphosphine Oxides

Abstract

Abstract An efficient procedure for the synthesis of alkynylphosphine oxides based on the oxidative alkynylation of secondary phosphine oxides with copper acetylides was developed. Activation with molecular oxygen in the presence of either a mixture of 1,2‐dimethylimidazole and triethylamine or N ‐methylimidazole alone enabled the formal umpolung of the poorly nucleophilic copper acetylides, which were coupled with phosphine oxides under remarkably mild conditions. Notable features of this procedure are the availability of the starting materials, its user‐friendliness, and its mild conditions, which allow the synthesis of complex alkynylphosphine oxides.