Asparagine monohydrate

Asparagine Solution Dissolve 10 g of L-asparagine monohydrate in approximately 500 mL of water, and dilute with water to 1 L. 

Properties L(-)-Asparagine monohydrate White crystals. Mp 234—235C. Acid to litmus. Nearly insoluble in ethanol, methanol, ether and benzene soluble in acids and alkalies. 

FIGURE 9 Half-normal probability plots for L-asparagine monohydrate (data from Verbist et alfigure from Abrahams see text). 

Fig. 11.34. Morphology of a crystal of (S)-asparagine monohydrate grown in aqueous solution Left Pure material...

L-Asparagine monohydrate Aspartic acid L-Aspartic acid H00C-CH2-CH(NH2)-C00H... 

Asparagine 5794-13-8 /.-Asparagine monohydrate 6899-03-2 Aspartic acid 56-84-8 L-Aspartic acid... 

Figure 3.20 EfTect of L-glutamic acid on the growth rate of 101 faces of L-asparagine monohydrate crystals. (Reproduced with permission from Black et al. 1986.)...

Black and Davey used Eq. (3.22) to study the effect of the tailor-made additive L-glutamic acid on L-asparagine monohydrate crystals. With the use of a linear adsorption isotherm, Eq. (3.22) fit the crystal growth rate data. Consistent with a structural model in which impurities are embedded in the growing crystal surface, the growth rate of the crystals tended to zero at a high L-glutamic level. 

Isolation, l-Aspartic acid is readily prepared from natural aspara ne in nearly the theoretical yield by Vickery and Pucher s (827) modification of Schiff s (680) method. A mixture containing 3.9 ml. of 3.5 N HCl per g. of natural asparagine monohydrate is refluxed for 3 hours, 3JS N NH4OH is added to bring the solution to pH 3, and 2 volumes of 95% ethanol are added. The resulting crystalline product is recrystallised from boiling water. 

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