title: Saturation transfer and chemical exchange measurements of the stereochemical drift occurring during the Wittig reaction.
abstract: The Wittig reaction of butylidenetriphenylphosphorane with benzaldehyde using LiHMDS as base in THF was studied. The stereochemical drift (different ratio obtained in alkenes versus oxaphosphetane intermediates) was followed by low-temperature 1D NMR techniques. A retro-Wittig reaction is demonstrated using 13C and 31P saturation transfer experiments and homonuclear DPFGSE-ROE techniques.
authors.affiliation: Institute of Analytical Chemistry, University of Leipzig, Johannisallee 29, D-4103 Leipzig, Germany.
authors.forename: Aurelia
authors.initials: A
authors.lastname: Pascariu
authors.forename: Mircea
authors.initials: M
authors.lastname: Mracec
authors.forename: Stefan
authors.initials: S
authors.lastname: Berger
mesh_terms: D001547:Benzaldehydes / Q000138:chemical synthesis / Q000737:chemistry*; D002247:Carbon Isotopes; D008094:Lithium / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D010753:Phosphoranes / Q000138:chemical synthesis / Q000737:chemistry*; D010759:Phosphorus Isotopes; D011522:Protons; D013237:Stereoisomerism; D013696:Temperature; D013997:Time Factors
chemical_list: D001547:Benzaldehydes; D002247:Carbon Isotopes; D010753:Phosphoranes; D010759:Phosphorus Isotopes; D011522:Protons; D008094:Lithium