123673-02-9Relevant articles and documents
Synthesis of chiral 2-oxo- and 2-thio-1,3,2-oxazaphospho-lidines via the asymmetric cyclization of l-serinoates with (thio)phosphoryl dichlorides
He, Zheng-Jie,Chen, Wen-Bin,Zhou, Zheng-Hong,Tang, Chu-Chi
, p. 3473 - 3479 (2000)
In this paper is described the asymmetric cyclization of L-serine derivatives with phosphoro(no-)dichloridates or their thio-analogues, and investigated the asymmetric induction effect of chiral carbon centre on the forming chiral phosphorus centre. Some cyclization products have been separated as a pure diastereomer and their configuration is preliminarily discussed.
Synthesis, Configuration, and Chemical Shift Correlations of Chiral 1,3,2-Oxazaphospholidin-2-ones Derived from l-Serine
Thompson,Charles M.,Frick, Jeffrey A.,Green, Diana L.C.
, p. 111 - 116 (2007/10/02)
The reaction between (S)-methyl N-benzylserinoate and phosphorous oxychloride leads to the diastereomeric chloro-1,3,2-oxazaphospholidin-2-ones.Reaction of the chloridates with alcohols or phenols in the presence of base affords the corresponding alkoxy (or aryloxy) derivatives (66-94percent), which were readily separated by standard chromatographic methods.The stereochemical arrangement of these compounds was established by NMR chemical shift correlations (carbon-13 and phosphorus-31) and single-crystal X-ray analysis.The trans geometry of the carbomethoxy and exocyclicphosphorus ligand resulted in approximately a 1 ppm upfield shift in the phosphorus-31 spectra relative to the cis isomer.The carbon-13 NMR spectra revealed an opposite trend to the heteroatom-bound alkyl region with most of the trans isomer signals appearing downfield (0.2-1.2 ppm) from the corresponding cis isomer.
