title: Surface-mediated reactions. 9. Selective oxidation of primary and secondary amines to hydroxylamines.
abstract: OXONE over silica gel or, in some cases, alumina has been found to oxidize the primary and secondary amines 3 selectively to the corresponding hydroxylamines 4, in either the presence or absence of a solvent. Treatment of Boc-protected L-lysine (6) under the latter conditions afforded hydroxylamine 7 in excellent yield. The trialkylamine 1a and pyridine (1b), in which selectivity is not an issue, were readily oxidized to the corresponding oxides 2 by OXONE over silica gel or alumina, as well as by (CH(3))(3)COOH over silica gel. Solvent-free oxidation assisted by microwave irradiation was more forcing, while still affording the hydroxylamines 4 selectively, and is the synthetic method of choice. The mechanistic aspects of these reactions are discussed.
authors.affiliation: Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, USA.
authors.forename: J D
authors.initials: JD
authors.lastname: Fields
authors.forename: P J
authors.initials: PJ
authors.lastname: Kropp
mesh_terms: D000537:Aluminum Oxide; D006898:Hydroxylamines / Q000737:chemistry*; D007202:Indicators and Reagents; D010084:Oxidation-Reduction; D013464:Sulfuric Acids; D013499:Surface Properties
chemical_list: D006898:Hydroxylamines; D007202:Indicators and Reagents; D013464:Sulfuric Acids; C048813:potassium peroxymonosulfuric acid; D000537:Aluminum Oxide