56558-30-6

67-56-1

6600-40-4

56558-30-6

L-norvaline (160 g, 1.34 mol) was dissolved in 28.5% hydrochloric acid solution (278 g) and diluted with methanol (500 ml). The reaction mixture was refluxed for 6 hours under the protection of inert atmosphere. After completion of the reaction, the solvent was removed by co-evaporation with toluene. The residue was treated with tert-butyl methyl ether (800 ml) at 50 °C. The resulting suspension was stirred at room temperature and subsequently filtered. The resulting white solid was washed with tert-butyl methyl ether to give 216 g of L-norvaline methyl ester hydrochloride in 97% yield.