Methyl L-isoleucinate hydrochloride

67-56-1

73-32-5

18598-74-8

Under ice bath conditions, 1 mL of sulfuryl chloride (SOCl2) was added slowly and dropwise to 5 mL of cooled methanol and the reaction mixture was stirred for 30 minutes. Subsequently, 1.01 g (8.55 mmol) of L-isoleucine was added to the mixture and the reaction was continued with stirring overnight. Upon completion of the reaction, the solvent was removed by distillation under reduced pressure. The resulting residue was purified by fast column chromatography with an eluent ratio of methanol/ether = 1/5 (v/v), resulting in the colorless oily crystalline product L-isoleucine methyl ester hydrochloride in 98.8% yield. The spectral data of the product were consistent with those reported in the literature.