title: Hydroxylamines as oxygen atom nucleophiles in transition-metal-catalyzed allylic substitution.
abstract: [reaction: see text] The viability of hydroxylamines as nucleophiles in transition-metal-catalyzed allylic substitutions was examined. We have found that the oxygen atom of hydroxylamines having an N-electron-withdrawing substituent (also known as hydroxamic acids) acts as a reactive nucleophile. The palladium-catalyzed O-allylic substitution of hydroxylamines with allylic carbonate afforded the linear hydroxylamines. The selective formation of the branched hydroxylamines was observed in iridium-catalyzed reaction. Regio- and enantioselective allylic substitution of the unsymmetrical phosphates with hydroxylamines was studied by using the iridium complex of chiral pybox ligand. The aqueous-medium reaction with hydroxylamines proceeded smoothly in the presence of Ba(OH)(2).H(2)O to give the branched products with good enantioselectivities.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.
authors.forename: Hideto
authors.initials: H
authors.lastname: Miyabe
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Yoshida
authors.forename: Masashige
authors.initials: M
authors.lastname: Yamauchi
authors.forename: Yoshiji
authors.initials: Y
authors.lastname: Takemoto
mesh_terms: D000498:Allyl Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D006898:Hydroxylamines / Q000737:chemistry*; D019216:Metals, Heavy / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*
chemical_list: D000498:Allyl Compounds; D006898:Hydroxylamines; D019216:Metals, Heavy; D009942:Organometallic Compounds; D010100:Oxygen