Synthesis and enantiomeric analysis of cyclotriphosphazene derivatives with one centre of chirality

A series of chiral cyclotriphosphazene compounds 2–9 in which the spiro 3-amino-1-propanoxy moiety provides the one centre of chirality have been synthesised and characterised by elemental analysis, MS, 1H and 31P NMR spectroscopies. The enantiomers of newly synthesised compounds have been analysed by the changes in the 31P NMR spectra on addition of a Chiral Solvating Agent (CSA), (S)-(+)-2,2,2-trifluoro-1-(9′-anthryl)ethanol. HPLC methods have been developed for the enantiomeric separations of chiral cyclotriphosphazenes containing one centre of chirality. It is found that chiral HPLC gave a good resolution of enantiomers of the racemic compounds 2–9 with resolution factors between 2.49 and 7.50 making them good candidates for enantiomeric separations and determination of absolute configuration.

In this work we have synthesized and characterised a series of compounds 2–9 in which the spiro 3-amino-1-propanoxy moiety provides the one centre of chirality. The enantiomers of newly synthesised compounds have been determined by changes in the 31P NMR spectra on addition of a Chiral Solvating Agent (CSA), (S)-(+)-2,2,2-trifluoro-1-(9′-anthryl)ethanol. The chiral HPLC methods using the Whelk-01 chiral column for the enantiomeric separations of these compounds have been developed in this study.Figure optionsDownload as PowerPoint slide