(2S,4R)-4-Fluoro­pyrrolidinium-2-carboxyl­ate

The crystal structure of the title compound, C₅H₈FNO₂, at 100 K, displays inter­molecular N—H...O hydrogen bonding between the ammonium and carboxyl­ate groups as a result of its zwitterionic nature in the solid state. The five-membered ring adopts an envelope conformation with the C atom at the 3-position as the flap. The compound is of inter­est with respect to the synthesis and structural properties of synthetic collagens. The absolute structure was determined by comparison with the commercially available material.