title: Iridium-catalyzed addition of aroyl chlorides and aliphatic acid chlorides to terminal alkynes.
abstract: Iridium complexes show high catalytic activity in intermolecular additions of acid chlorides to terminal alkynes to afford valuable (Z)-β-chloro-α,β-unsaturated ketones. Ligands in the catalytic system play a crucial role in this reaction. An N-heterocyclic carbene (NHC) is an efficient ligand for the addition of aroyl chlorides, while dicyclohexyl(2-methylphenyl)phosphine (PCy(2)(o-Tol)) is indispensable for the reaction of aliphatic acid chlorides. The addition reactions proceed regio- and stereoselectively with suppression of decarbonylation and β-hydrogen elimination, which have been two major intrinsic problems in transition-metal-catalyzed reactions. Stoichiometric reactions of active iridium catalysts with aroyl chlorides and aliphatic acid chlorides are carried out to gain insights into the reaction mechanisms.
authors.affiliation: Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Iwai
authors.forename: Tetsuaki
authors.initials: T
authors.lastname: Fujihara
authors.forename: Jun
authors.initials: J
authors.lastname: Terao
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Tsuji