title: Ruthenium-catalyzed hydrative cyclization of 1,5-enynes.
abstract: A ruthenium-catalyzed hydrative cyclization of enynes has been developed. The reaction converts a range of 1,5-enynes bearing terminal alkyne and Michael acceptor moieties into cyclopentanone derivatives. From extensive catalyst screening experiments, a trinuclear ruthenium complex, [Ru3(dppm)3Cl5]PF6, has been identified to be an effective catalyst in mediating the 1,1-difunctionalization of alkynes. It is proposed that this novel umpolung reaction proceeds through the formation of a ruthenium vinylidene, anti-Markovnikov hydration, and intramolecular Michael addition of an acyl ruthenium to the alkene.
authors.affiliation: Department of Chemistry, Princeton University, Princeton, New Jersey, 08544-1009, USA.
authors.forename: Yiyun
authors.initials: Y
authors.lastname: Chen
authors.forename: Douglas M
authors.initials: DM
authors.lastname: Ho
authors.forename: Chulbom
authors.initials: C
authors.lastname: Lee