title: Asymmetric hydrogenation of pyridinium salts with an iridium phosphole catalyst.
abstract: Iridium-catalyzed asymmetric hydrogenation of N-alkyl-2-alkylpyridinium salts provided 2-aryl-substituted piperidines with high levels of enantioselectivity. Simple benzyl and other alkyl groups successfully activated the challenging pyridine substrates toward hydrogenation. The use of the unusual chiral-phosphole-based MP(2) -SEGPHOS was the key to the success of this approach which provides a versatile and practical procedure for the synthesis of chiral piperidines.
authors.affiliation: Department of Chemistry and Chemical Biology and Department of Medicinal Chemistry, Rutgers, The State University of New Jersey, 610 Taylor Road, Piscataway, New Jersey, 08854 (USA).
authors.forename: Mingxin
authors.initials: M
authors.lastname: Chang
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Huang
authors.forename: Shaodong
authors.initials: S
authors.lastname: Liu
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Chen
authors.forename: Shane W
authors.initials: SW
authors.lastname: Krska
authors.forename: Ian W
authors.initials: IW
authors.lastname: Davies
authors.forename: Xumu
authors.initials: X
authors.lastname: Zhang
mesh_terms: D002384:Catalysis; D006573:Heterocyclic Compounds, 1-Ring / Q000737:chemistry*; D006865:Hydrogenation; D015394:Molecular Structure; D009943:Organophosphorus Compounds / Q000737:chemistry*; D011726:Pyridinium Compounds / Q000737:chemistry*; D012492:Salts / Q000737:chemistry
chemical_list: D006573:Heterocyclic Compounds, 1-Ring; D009943:Organophosphorus Compounds; D011726:Pyridinium Compounds; D012492:Salts
keywords: asymmetric catalysis; heterocycles; hydrogenation; iridium; stereoselectivity