Synthesis
(2) Preparation of glycine methyl ester hydrochloride: 60 mL of methanol was added to a 100 mL round-bottomed flask under ice-bath conditions, followed by the slow dropwise addition of 4 mL of sulfoxide chloride (SOCl2) through a constant-pressure dropping funnel (with a drying tube on top). The resulting off-gas was absorbed using NaOH solution. After stirring the reaction mixture for 1 h, 8 mmol of glycine was added and stirring was continued for 30 min at room temperature. Subsequently, the reaction system was warmed up to 66 °C and refluxed for 6 hours. The progress of the reaction was monitored by thin layer chromatography (TLC) using 2% ninhydrin ethanol solution as a color developer until the disappearance of the raw material spot. After completion of the reaction, the solvent was removed by evaporation to give glycine methyl ester hydrochloride in 100% yield.
Purification Methods
Crystallise the ester salt from MeOH. [Werbin & Spoerri J Am Chem Soc 69 1682 1947, Beilstein 4 H 340, 4 III 1116.]
References
[1] Synthetic Communications, 1998, vol. 28, # 3, p. 471 - 474
[2] European Journal of Organic Chemistry, 2012, # 29, p. 5774 - 5788,15
[3] European Journal of Organic Chemistry, 2012, # 29, p. 5774 - 5788
[4] Patent: US2014/206741, 2014, A1. Location in patent: Paragraph 0131
[5] European Journal of Organic Chemistry, 2017, vol. 2017, # 3, p. 695 - 703
