Saturation transfer and chemical exchange measurements of the stereochemical drift occurring during the Wittig reaction.
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.
Pascariu
Aurelia
A
Institute of Analytical Chemistry, University of Leipzig, Johannisallee 29, D-4103 Leipzig, Germany.
Mracec
Mircea
M
Berger
Stefan
S
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
D001547:Benzaldehydes; D002247:Carbon Isotopes; D010753:Phosphoranes; D010759:Phosphorus Isotopes; D011522:Protons; D008094:Lithium