Synthetic Methods and Reactions. Part 106. Suppression of anchimerically assisted rearrangement products in the synthesis of α-fluorocarboxylic acids from α-amino acids with 48:52 (w/w) hydrogen fluoride/pyridine [1]

Anchimerically assisted rearrangement, observed in the fluorination of some α-amino acids with 70 : 30 (w/w) hydrogen fluoride/pyridine (by weight) in the presence of NaNO₂, is substantially or fully suppressed by using the less acidic reagent 48 : 52 (w/w) hydrogen fluoride/pyridine.