Click-alkynylation of N- and P-nucleophiles by oxidative cross-coupling with alkynylcopper reagents: a general synthesis of ynamides and alkynylphosphonates

Nitrogen- and phosphorus-based nucleophiles can be smoothly transformed to the corresponding heteroatom-substituted alkynes by simple reaction at room temperature and under an oxygen atmosphere with copper acetylides. These stable, readily available, polymers act as especially efficient reagents for the introduction of an alkyne group under remarkably mild oxidative conditions which allow for their formal umpolung. Chelating ligands such as TMEDA and N-methylimidazole are efficient organic promoters, allowing for clean and fast oxidative cross-couplings, even with complex substrates.