Use of shift reagent with MTPA derivatives in 19F NMR spectrocopy: IV—Determination of enantiomeric composition for a variety of secondary cycloalkanols. A survey

Chiral secondary cycloalkanols (monocyclic alcohols) are derivatized to the corresponding (R)-α-methoxy-α-trifluoromethyl-α-phenylacetic acid (R)-MTPA] esters and analysed by ¹⁹F NMR in the presence of tris(6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionato) europium(III) Eu(fod)₃]. Using this method the enantiomeric composition can be measured for several cyclopentanols, cyclohexanols and cycloheptanols, with a variety of substitution patterns. It is shown that a mixture of four stereoisomeric cycloalkanols, such as cis and trans disubstituted alcohols, can be analysed simultaneously.