Dissolve 10g of (1S, 4R)-4-aminocyclopent-2-ene-1-carboxylic acid methyl ester tartrate in 50mL of methanol, add triethylamine to neutralize to Ph6-7, add 10mL of water and cool to -20 , 5mL of lithium hydroxide aqueous solution (containing 0.16g of lithium hydroxide) was added dropwise, immediately after the reaction was neutralized with acetic acid to pH 3-4, the organic solvent was vortexed and diluted with tetrahydrofuran, the salt was filtered off and vortexed to obtain (1S,4R)-4-Amino-2-cyclopenten-1-carboxylic Acid Hydrochloride 3.6 g, yield 83.7%.
