L-Malic Acid → HCID 178512932, compound

Participants

Reaction Steps

To an aqueous solution of free L-arginine (content of L-arginine: 0.05 mole) is added L-malic acid (3.35 g, 1/2 mole per 1 mole of L-arginine) (pH value of the reaction mixture: 7.0). The resulting reaction mixture is concentrated under reduced pressure until the total amount of the mixture becomes 15.2 g, (while the concentrated mixture is allowed to stand at room temperature overnight, no crystal precipitates). To the solution is added methanol (4 ml) and further is added seed crystals of neutral L-arginine DL-malate, and the mixture is allowed to stand overnight. The precipitated crystals are collected by filtration and washed with a 80% aqueous methanol solution and are air-dried at 60° C. overnight to give neutral L-arginine L-malate anhydrate (8.6 g, yield: 71.3%) as colorless granular or prismatic crystal. m.p. 219° C. (decomp.)

Provenance & Evidence