Alanin Hydrochlorid

To a solution of l. 47 g (0.03 mol) of sodium cyanide and 4.73 g (0.03 mol) of (-)-(.S)-x-methylbenzylamine hydrochloride in 5 mL of cold water is added 1 g (8.3 mmol) of free ( - )-(.S )-a-mcthylbcnzylaininc in 200 mL of CHjOH. 1.32 g (0.03 mol) of acetaldehyde is added at 0°C and the clear solution is kept at r.t. for five days. After evaporation of the solvent in vacuo, the residue is dissolved in 50 mL of 1 N HC1 and the solution is extracted twice with diethyl ether. After addition of 12 N HCl to adjust the acid concentration to approximately 5 N, the solution is retluxed for 6 h. The HCl is evaporated in vacuo and the residue is dried over sodium hydroxide. The crude. V-x-methylbenzylalaninc hydrochloride is dissolved in 200 mL of 50% ethanol and the pH is adjusted to 6.0 with NaHCOj. To this solution, 3.5 g of palladium hydroxide is added. After hydrogenolysis for 10 h, the catalyst is filtered off and washed with hot water. The filtrate is concentrated to 30%, and the pH is adjusted to 1 with dilute IIC1. The solution is evaporated to dryness and the alanine hydrochloride is extracted with three 20-inL portions of absolute ethanol. After cooling overnight at — 50°C, the precipitated salt is filtered. Pyridine is added to the alcoholic solution to precipitate crude alanine, which is dissolved in 2.5 mL of water. The pH is adjusted with pyridine to 5.5-6.0, and 10 mL of absolute ethanol arc added yield 0.45 g (17% over four steps) mp 290 C [a] 7 + 13.13 (0 = 2.32. 6 N IICi). 

Dioxane p-Dioxane (8) 1,4-Dioxane (9) (123-91-1) 3-Aminopropanoic acid hydrochloride /3-Alanine, hydrochloride (8, 9) (6057-90-5)... 

Alkyl-substituted oxazoles have been found to react with maleic acid or its anhydride in a diene synthesis to yield substituted pyridine readily converted to pyridoxine (39). In this route, ethyl d, 1-alaninate hydrochloride is treated with formic-acetic anhydride to yield ethyl N-formyl d,1-alaninate (78%). This compound is refluxed in chloroform with phosphorous pentoxide (40), quenched with aqueous potassium hydroxide, and the organic layer distilled to give 4-methyl-5-ethoxyoxazole (I) (60%). The resulting oxazole (I) is condensed readily with a number of appropriate dienophiles to form 2-methyl-3-hydroxy-4,5-disubstituted-pyridines containing substituents (III, a, b, c) which could be converted to pyridoxine as follows ... 

To 35 g of ethyl a-alaninate hydrochloride is added 10 g of formamide and the resulting mixture is heated slowly to 105°C over a period of 30 to 45 min. After heating at 105°C for 10 min, about 75 ml of toluene is added. After standing for about 1 h, the mixture is then refluxed for about 6 h. After cooling the ammonium chloride formed is removed and the resulting solution is evaporated to remove the solvent. The ethyl N-formyl-a-alaninate is obtained by distillation at 100°C. 

For extraction of the 170 CS tensor components, analysis of stationary NMR spectra is one of the most straightforward methods. Figure 8 shows the experimental and calculated 170 stationary NMR spectra of [170]-L-alanine hydrochloride observed and calculated at (A) 9.4, (B) 11.7 and (C) 21.6 T.54... 

Noordik JH, Jeffrey GA (1977) Acta Crystallogr, Sect B 33 403 ALAHCL. L-Alanine hydrochloride (C3H8N02, Cl-). Blasio B di, Pavone V, Pedone C (1977) Cryst Struct Commun 6 745... 

Sketch the pH curves for the titration of lOOml of 0.1 Af alanine hydrochloride with KOH in the (a) absence and (b) presence of excess formaldehyde. 

Lead oxide is used in an early procedure for the conversion of an amino acid hydrochloride into the free amine. A solution of alanine hydrochloride in water is... 

L(+)-alanine, mp 297C (decomposes). D(-)-alanine, mp 295C (decomposes). L(+)-alanine hydrochloride prisms, mp 204C (decomposes). 

Japanese workers76 claim the superiority of a phosgene-triethylamine mixture (ratio 1 2) over other conventional dehydrating agents. Thus, they devised a novel synthesis of 4-methyl-5-alkoxyoxazole-2-carboxylic acid esters (17) by condensation of alkyl alaninate hydrochloride with diethyl or dimethyl oxalate followed by cyclization of the product (16). 

In the radioactive tracer experiments H- or C-labeled D- or L-Alanine hydrochloride (Ala HCl) in DMF solutions were equilibrated with finely powdered d- or /-quartz Differences in rates of radioactive disintegrations of solutions before and after equilibration gave a measure of the amount of Ala HCl adsorbed on the quartz samples. In general, r/-quartz preferentially adsorbed D-Ala HCl and the /-quartz Z,-Ala HCl to the extents of 1-1.8%. These experiments used finely powdered samples of d- and /-quartz which had been prepared from known morphological handedness and optical rotation, but the authors failed to mention how the Brasilian twins (if any) were removed from quartz samples They did note that samples of quartz were prepared by hydrothermal growth and that crystals were checked... 

Adsorption of and C-labeled D- and L-alanine hydrochloride on d- and /-quartz crystals (modified data adapted from Bonner et al. 

Figure 50 depicts the pH-logCj diagram of an alanine hydrochloride (H2ACCP)... 

Figure 51 shows the pH-logCi diagram of an alanine hydrochloride (H2ArCl ) solution at 10 " mol Even at this low concentration, the acid appears as a strong monobasic acid, and the second protolysis step can be neglected, i.e., the equilibrium concentration of is very small compared to those of HB , H2B and HsO" ". Thus, the pH can be approximately read as the pH-coordinate of Pi, completely as in the case of a strong monobasic acid, and the pH can be approximately calculated with Eq. (132). 

Phosphonic acid amide esters. A soln. of ethyl [l-[[(phenylmethoxy)carbonyl]amino]-2-methylpropyl]phosphinate in acetonitrile under argon treated with bis(trimethyl-silyl)acetamide, followed after 1 min by L-alanine hydrochloride methyl ester, CCI4, and Et3N, the soln. stirred at room temp, for 30 min, cooled to 0°, and quenched with methanol N-[ethoxy[ 1 -[[(phenylmethoxy)carbonyl]am no]-2-methylpropyl]-... 

K. Yamada, T. Shimizu, T. Yamazaki, S. Ohkei, Determination of the orientations for the NMR tensors in a polycrystaHine L-alanine hydrochloride, Solid State Nucl. Magn. Reson. 33 (2008) 88. 

Starting with alanine hydrochloride (its structure at low pH in hydrochloric acid is shown in Figure 17.2), write equations for its reaction with one equivalent of sodium hydroxide and then with a second equivalent of sodium hydroxide. 

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