Determination of absolute configuration of α-hydroxyphosphonates by 31P NMR spectroscopy of corresponding mosher esters

doi:10.1016/S0040-4020(01)81758-0

Tetrahedron

Volume 50, Issue 34, 22 August 1994, Pages 10253-10264

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Abstract

(R)-MTPA esters of α-hydroxyphosphonates 1a-h of known absolute configuration were prepared and their ³¹P NMR spectra were recorded. The chemical shifts of the ³¹P signals of the derivatized (S)-alcohols are consistently downfield relative to the signals of the corresponding (R)-alcohols. A variety of racemic and diastereomeric α-hydroxyphosphonates 1i-o and their (R)-MTPA esters were prepared. The ³¹P chemical shift differences are large enough to securely assign absolute configurations to α-hydroxyphosphonates.

The absolute configuration of α-hydroxyphosphonates was determined by derivatisation with Mosher reagent and application of ³¹P NMR spectroscopy.

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Determination of absolute configuration of α-hydroxyphosphonates by 31P NMR spectroscopy of corresponding mosher esters

Abstract

Tetrahedron

Tetrahedron: Asymmetry

Tetrahedron Lett.

Tetrahedron: Asymmetry

Tetrahedron: Asymmetry

J. Chem Soc., Chem Commun.

Tetrahedron Lett.

Tetrahedron: Asymmetry

Tetrahedron Lett.

Tetrahedron Lett.

J. Org. Chem.

J. Am. Chem. Soc.

Chem. Rev.

Determination of absolute configuration of α-hydroxyphosphonates by ³¹P NMR spectroscopy of corresponding mosher esters