An anti-Markovnikov Hydration Reaction of Terminal Alkynes Using Ruthenium Complexes

Herzon et al. have reported the anti-Markovnikov hydration reaction of terminal alkynes using ruthenium complexes. According to their results, terminal alkynes can be directly converted to aldehydes via an anti-Markovnikov hydration reaction by using a ruthenium complex prepared from tris(acetonitrile)cyclopentadienylruthenium(II) hexafluorophosphate (1) and a bipyridyl ligand (2). This reaction proceeds under milder conditions compared to other conventional reactions using ruthenium catalysts and it shows high reactivity even with the addition of only 2 mol% of the ruthenium catalyst at room temperature. In addition, this reaction can be applied to various substances such as sterically hindered terminal alkynes, a hydroxy group or an amide group-substituted terminal alkynes and conjugated enynes. Thus, this synthetic method is expected to be used as an efficient anti-Markovnikov hydration reaction.