title: β-Carboline Amides as Intrinsic Directing Groups for C(sp2)-H Functionalization.
abstract: Many site-selective palladium-catalyzed C-H functionalization methods require directing groups. We report here β-carboline amides as intrinsic directing groups for C(sp2)-H functionalization. Various substrates including the natural product alangiobussinine and the marinacarboline core structure were functionalized using carboline-directed δ-C(sp2)-H alkynylations. This transformation proceeds under mild conditions and is compatible with a wide variety of β-arylethamines. δ-Alkynylation of β-arylethamines via a six-membered palladacycle is favored over γ-C(sp2)-H bond functionalization when both positions are accessible. The versatility of β-carboline amides as directing groups is evidenced by other δ-C(sp2)-H functionalizations such as alkenylation, arylation, and C-N bond formation.
authors.affiliation: Department of Chemistry, University of California , Berkeley, California 94720, United States.
authors.forename: Hélène M-F
authors.initials: HM
authors.lastname: Viart
authors.affiliation: Department of Chemistry, University of California , Berkeley, California 94720, United States.
authors.forename: Andreas
authors.initials: A
authors.lastname: Bachmann
authors.affiliation: Department of Chemistry, University of California , Berkeley, California 94720, United States.
authors.forename: William
authors.initials: W
authors.lastname: Kayitare
authors.affiliation: Department of Chemistry, University of California , Berkeley, California 94720, United States.
authors.forename: Richmond
authors.identifier: 0000-0002-0028-6323
authors.initials: R
authors.lastname: Sarpong
mesh_terms: D000577:Amides / Q000737:chemistry*; D002243:Carbolines / Q000737:chemistry*; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D015394:Molecular Structure
chemical_list: D000577:Amides; D002243:Carbolines