Chemical Properties
White or off-white crystal
Uses
DL-Aspartic acid dimethyl ester hydrochloride is an aspartic acid derivative[1].
Synthesis
106.8 g (0.8 mol) of D-aspartic acid and 700 ml of methanol were added to the reaction vessel, and 84.4 ml (1.2 mol) of thionyl chloride was slowly added dropwise under stirring conditions, with the reaction temperature controlled at 0 °C. After the dropwise addition, the reaction mixture was warmed up to room temperature (about 29°C) and the reaction was continued with stirring for 30 hours. Upon completion of the reaction, excess methanol and thionyl chloride were removed from the reaction solution by distillation. The remaining oily substance was dissolved in 3.5 times the volume of ether for crystallization to obtain white crystals. After filtration, the crystals were washed with ether three times and dried to finally obtain 107.8 g of white solid product DL-aspartic acid dimethyl ester hydrochloride.
Purification Methods
Crystallise it from absolute MeOH. [Kovach et al. J Am Chem Soc 107 7360 1985.] The diethyl ester has pK25 6.4.
References
[1] Luckose F, et al. Effects of amino acid derivatives on physical, mental, and physiological activities. Crit Rev Food Sci Nutr. 2015;55(13):1793-1144. DOI:
10.1080/10408398.2012.708368
