Stereoisomere Aromastoffe XXVII. Optisch reine Carbonsäurealkan-3-ylester - Darstellung und Eigenschaften

Diastereomeric (S)-O-acetyllactic acid alkan-3-yl esters were separated by liquid chromatography to yield optically pure alkan-3-ols by reductive cleavage. The absolute configuration of alkan-3-ol enantiomers was concluded from the1H-NMR data of their diastereomeric esters with optically pure (R)-2-phenylpropionic acid and (R)-α-methoxy-α-(trifluoromethyl)phenylacetic acid. The1H-NMR spectroscopic behaviour of diastereomeric (S)-O-acetyllactic acid alkan-3-yl ester was found to be very similar to those of the corresponding (R) 2-methoxy-2-(trifloromethyl)phenyl acetic acid esters; the direct elucidation of the absolute configuration of (S)-O-acetyl-lactic acid alkan-3-yl esters was demonstrated. The esterification of alkan-3-ols (C6–Cn8) with acetic acid, butyric acid, hexanoic acid and octanoic acid respectively yields 12 pairs of optically pure mirror images. Their sensory properties are discussed.