Abstract
The 31P NMR spectra of a series of diastereomeric 2-methoxy-2-oxo-1,2-oxaphospholan-3-ols are analyzed. A downfield shift Δδ(31P) > 1 ppm is specific for the isomer with the P[dbnd]O and HO[sbnd]C-3 groups in the cis configuration with respect to the trans isomer.