Broad-Spectrum Catalysts for the Ambient Temperature Anti-Markovnikov Hydration of Alkynes

Anti-Markovnikov alkyne hydration provides a valuable route to aldehydes. Half-sandwich ruthenium complexes ligated by 5,5'-bis(trifluoromethyl)-2,2'-bipyridine are remarkably active for this transformation. In the presence of 2 mol% metal, a wide range of functionalized aliphatic and aromatic alkynes are hydrated in high yield at ambient temperature.