title: Challenging nickel-catalysed amine arylations enabled by tailored ancillary ligand design.
abstract: Palladium-catalysed C(sp(2))-N cross-coupling (that is, Buchwald-Hartwig amination) is employed widely in synthetic chemistry, including in the pharmaceutical industry, for the synthesis of (hetero)aniline derivatives. However, the cost and relative scarcity of palladium provides motivation for the development of alternative, more Earth-abundant catalysts for such transformations. Here we disclose an operationally simple and air-stable ligand/nickel(II) pre-catalyst that accommodates the broadest combination of C(sp(2))-N coupling partners reported to date for any single nickel catalyst, without the need for a precious-metal co-catalyst. Key to the unprecedented performance of this pre-catalyst is the application of the new, sterically demanding yet electron-poor bisphosphine PAd-DalPhos. Featured are the first reports of nickel-catalysed room temperature reactions involving challenging primary alkylamine and ammonia reaction partners employing an unprecedented scope of electrophiles, including transformations involving sought-after (hetero)aryl mesylates for which no capable catalyst system is known.
authors.affiliation: Department of Chemistry, Dalhousie University, 6274 Coburg Road, PO Box 15000, Halifax, Nova Scotia, Canada B3H 4R2.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Lavoie
authors.affiliation: Department of Chemistry, Dalhousie University, 6274 Coburg Road, PO Box 15000, Halifax, Nova Scotia, Canada B3H 4R2.
authors.forename: Preston M
authors.initials: PM
authors.lastname: MacQueen
authors.affiliation: Department of Chemistry, Dalhousie University, 6274 Coburg Road, PO Box 15000, Halifax, Nova Scotia, Canada B3H 4R2.
authors.forename: Nicolas L
authors.initials: NL
authors.lastname: Rotta-Loria
authors.affiliation: Department of Chemistry, Dalhousie University, 6274 Coburg Road, PO Box 15000, Halifax, Nova Scotia, Canada B3H 4R2.
authors.forename: Ryan S
authors.initials: RS
authors.lastname: Sawatzky
authors.affiliation: Department of Chemistry, Dalhousie University, 6274 Coburg Road, PO Box 15000, Halifax, Nova Scotia, Canada B3H 4R2.
authors.forename: Andrey
authors.initials: A
authors.lastname: Borzenko
authors.affiliation: Department of Chemistry, Dalhousie University, 6274 Coburg Road, PO Box 15000, Halifax, Nova Scotia, Canada B3H 4R2.
authors.forename: Alicia J
authors.initials: AJ
authors.lastname: Chisholm
authors.affiliation: Department of Chemistry, Dalhousie University, 6274 Coburg Road, PO Box 15000, Halifax, Nova Scotia, Canada B3H 4R2.
authors.forename: Breanna K V
authors.initials: BK
authors.lastname: Hargreaves
authors.affiliation: X-Ray Crystallography Laboratory, Department of Chemistry, University of Alberta, Edmonton, Alberta Canada T6G 2G2.
authors.forename: Robert
authors.initials: R
authors.lastname: McDonald
authors.affiliation: X-Ray Crystallography Laboratory, Department of Chemistry, University of Alberta, Edmonton, Alberta Canada T6G 2G2.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Ferguson
authors.affiliation: Department of Chemistry, Dalhousie University, 6274 Coburg Road, PO Box 15000, Halifax, Nova Scotia, Canada B3H 4R2.
authors.forename: Mark
authors.initials: M
authors.lastname: Stradiotto