title: Chemoselective hydroamination of vinyl arenes catalyzed by an NHC-amidate-alkoxide Pd(II) complex andp-TsOH.
abstract: The hydroamination of various substituted vinyl arenes with benzenesulfonamide was explored using an NHC-amidate-alkoxide palladium catalyst in conjunction withp-TsOH. Utilizing halide-substituted and electron-rich vinyl arenes, this methodology selectively furnished the cross-coupled hydroamination products in moderate to excellent yields in a Markovnikov fashion while greatly reducing undesired acid-catalyzed homocoupling of the vinyl arenes. Electron-rich vinyl arenes typically required milder conditions than electron-poor ones. While most effective for para-substituted substrates, the catalyst system also furnished the desired products from ortho- and meta-substituted vinyl arenes with high chemoselectivities.
authors.affiliation: Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Giles
authors.forename: Justin
authors.initials: J
authors.lastname: O'Neill
authors.forename: Joo Ho
authors.initials: JH
authors.lastname: Lee
authors.forename: Michael K
authors.initials: MK
authors.lastname: Chiu
authors.forename: Kyung Woon
authors.initials: KW
authors.lastname: Jung
keywords: Brønsted acid; Hydroamination; Palladium catalyst; Sulfonamide; Vinyl arenes
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