title: 31P NMR and computational studies on stereochemistry of conversion of phosphoramidate diesters into the corresponding phosphotriesters.
abstract: 31P NMR spectroscopy was used to investigate a stereochemical course of a nitrite-promoted conversion of phosphoramidate diesters into the corresponding phosphotriesters. It was found that this reaction occurred with almost complete epimerization at the phosphorus center and at the C1 atom in the amine moiety. On the basis of the 31P NMR data, a plausible mechanism for the reaction was proposed. The density functional theory calculation of the key step of the reaction, i.e., breaking of the P-N bond and formation of the P-O bond, suggested a one-step S(N)2(P) process with retention of configuration at the phosphorus center.
authors: Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm, Sweden.
authors: Linda
authors: L
authors: Söderberg
authors: Gaston
authors: G
authors: Lavén
authors: Marcin
authors: M
authors: Kalek
authors: Jacek
authors: J
authors: Stawinski
mesh_terms: D000577:Amides / Q000737:chemistry*; D004952:Esters / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008968:Molecular Conformation; D009573:Nitrites / Q000737:chemistry*; D010756:Phosphoric Acids / Q000737:chemistry*; D010759:Phosphorus Isotopes / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000577:Amides; D004952:Esters; D009573:Nitrites; D010756:Phosphoric Acids; D010759:Phosphorus Isotopes; C011067:phosphoramidic acid