SIMPLE SYNTHESIS OF OPTICALLY-ACTIVE 2-FLUOROPROPANOIC ACID AND ANALOGS OF HIGH ENANTIOMERIC PURITY

A very simple synthesis of optically active 2-fluoropropanoic acid 1 (R=CH3, R'=H) and analogs of high enantiomeric purity was developed using the sulfonate 2 of the corresponding optically active 2-hydroxycarboxylic esters and potassium fluoride in formamide. Thus methyl (R)-2-fluoropropanoate (1, R=CH3, R'=CH3) was prepared in an optic purity of 96% from the mesylate of methyl (S)-lactate (ee 97.4%) and isolated in 83% yield.