title: New route to the ergoline skeleton via cyclization of 4-unsubstituted indoles.
abstract: A new route to the ergoline skeleton has been developed that does not require prior functionalization of the indole 4-position. The indole nucleus is introduced late in the synthesis to allow for eventual efficient introduction of substituents in this region. Key steps include Negishi coupling of a three-carbon chain to a bromonicotinate ester, Fischer indole synthesis to facilitate incorporation of substituents via phenylhydrazines, and Pd-catalyzed cyclization to form the ergoline C ring.
authors: Department of Chemistry, San Diego State University, San Diego, California 92182, USA.
authors: Scott D
authors: SD
authors: Burley
authors: Vicky V
authors: VV
authors: Lam
authors: Frederick J
authors: FJ
authors: Lakner
authors: B Mikael
authors: BM
authors: Bergdahl
authors: Matthew A
authors: MA
authors: Parker
mesh_terms: D002384:Catalysis; D003500:Cyclization; D004873:Ergolines / Q000138:chemical synthesis* / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D015394:Molecular Structure; D009525:Niacin / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry*; D010659:Phenylhydrazines / Q000737:chemistry*
chemical_list: D004873:Ergolines; D007211:Indoles; D010659:Phenylhydrazines; D009525:Niacin; D010165:Palladium