title: Aryl amination using ligand-free Ni(II) salts and photoredox catalysis.
abstract: Over the past two decades, there have been major developments in transition metal-catalyzed aminations of aryl halides to form anilines, a common structure found in drug agents, natural product isolates, and fine chemicals. Many of these approaches have enabled highly efficient and selective coupling through the design of specialized ligands, which facilitate reductive elimination from a destabilized metal center. We postulated that a general and complementary method for carbon-nitrogen bond formation could be developed through the destabilization of a metal amido complex via photoredox catalysis, thus providing an alternative approach to the use of structurally complex ligand systems. Here, we report the development of a distinct mechanistic paradigm for aryl amination using ligand-free nickel(II) salts, in which facile reductive elimination from the nickel metal center is induced via a photoredox-catalyzed electron-transfer event.
authors.affiliation: Merck Center for Catalysis at Princeton University, Princeton, NJ 08544, USA.
authors.forename: Emily B
authors.initials: EB
authors.lastname: Corcoran
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Pirnot
authors.affiliation: Department of Process Chemistry, Merck Research Laboratories, Rahway, NJ 07065, USA.
authors.forename: Shishi
authors.initials: S
authors.lastname: Lin
authors.affiliation: Department of Process Chemistry, Merck Research Laboratories, Rahway, NJ 07065, USA.
authors.forename: Spencer D
authors.initials: SD
authors.lastname: Dreher
authors.affiliation: Department of Process Chemistry, Merck Research Laboratories, Rahway, NJ 07065, USA.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: DiRocco
authors.affiliation: Department of Process Chemistry, Merck Research Laboratories, Rahway, NJ 07065, USA.
authors.forename: Ian W
authors.initials: IW
authors.lastname: Davies
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. dmacmill@princeton.edu sbuchwal@mit.edu.
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Buchwald
authors.affiliation: Merck Center for Catalysis at Princeton University, Princeton, NJ 08544, USA. dmacmill@princeton.edu sbuchwal@mit.edu.
authors.forename: David W C
authors.initials: DW
authors.lastname: MacMillan