title: Copper-catalyzed asymmetric synthesis of tertiary α-hydroxy phosphonic acid derivatives with in situ generated nitrosocarbonyl compounds as the oxygen source.
abstract: α-Hydroxy phosphonic acids and their derivatives are highly bioactive structural motifs. It is now reported that these compounds can be accessed through the copper-catalyzed direct α-oxidation of β-ketophosphonates using in situ generated nitrosocarbonyl compounds as an electrophilic oxygen source. These reactions proceeded in high yields (up to 95 %) and enantioselectivities (up to >99 % ee) for both cyclic as well as acyclic substrates. This method was also applied for the synthesis of α,β-dihydroxy phosphonates and β-amino-α-hydroxy phosphonates.
authors.affiliation: Molecular Catalyst Research Center, Chubu University, Kasugai, Aichi 487-8501 (Japan) http://www3.chubu.ac.jp/catalyst/. biplabmaji@isc.chubu.ac.jp.
authors.forename: Biplab
authors.initials: B
authors.lastname: Maji
authors.forename: Hisashi
authors.initials: H
authors.lastname: Yamamoto
mesh_terms: D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D007093:Imidazoles / Q000737:chemistry; D008698:Mesylates / Q000737:chemistry; D008968:Molecular Conformation; D063065:Organophosphonates / Q000138:chemical synthesis / Q000737:chemistry*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D007093:Imidazoles; D008698:Mesylates; D063065:Organophosphonates; C490207:oxaline; D003300:Copper; C012077:trifluoromethanesulfonic acid; D010100:Oxygen
keywords: asymmetric synthesis; bisoxazoline; copper; oxidation; phosphonic acids