Methyl /9-methoxypropionate

C) dl-Serine.—One-half (350-375 g.) of the crude bromo-methoxypropionic acid prepared from the saponification of 800 g. of methyl a-bromo-/3-methoxypropionate is heated with 3.5 1. of concentrated ammonium hydroxide in a glass-lined autoclave (Note T4) for ten to fifteen hours at 90-100°, and the solution from the bomb is concentrated to a thick syrup under reduced pressure (Note 15). Two liters of water is added, and the solution is concentrated to dryness. The cake is dissolved in 1.5 1. of 48 per cent hydrobromic acid and refluxed for two and one-half hours. The resulting dark solution is concentrated to a volume of about 500 cc. and then cooled under the tap. The... 

The crude ester may be used directly in the preparation of serine. However, greater ease of purification and slightly better yields make it advantageous to prepare the free acid. Pure methyl a-bromo-j8-methoxypropionate is obtained by fractionally distilling the crude material under reduced pressure through a Widmer column. From 100 g. of crude material there is obtained 80-90 g. of pure ester, b.p. 73-75°/6 mm., n 1.4586. 

Methanolysis of 0-propiolactone with a trace of hydroxide catalyst gives a good yield of methyl 3 -hydroxypropionic acid, but with an equimolecular quantity of sodium methoxide the product is sodium 3-methoxypropionate (equation 48) (64hc(19-2)729). 

Bonner et al. found that the hydrogenolysis of optically active methyl or ethyl atrolac-tates (48, X = OH) in refluxing ethanol with large amounts of Raney Ni proceeded largely with retention of configuration methyl D-(+)-2-phenyl-2-methoxypropionate... 

A mixture of 65 g. (0.75 mole) of methyl acrylate and 25 g. (0.78 mole) of methanol is cooled, and 2 drops of a concentrated solution of sodium methoxide in methanol is added. The mixture is held in the temperature range 30-35° by external cooling until the temperature shows no further tendency to rise (about 10 minutes). The reaction mixture is then neutralized with acetic acid and distilled. Redistillation gives 68 g. (77%) of methyl yS-methoxypropionate boiling at 137-143°. 

The addition of methanol to propiolactono in the presence of an equimoJeoular quantity of eodium methylate givee S-methoxypropionic aoid In a high Id. Barnett and Rylander have explained the mechanism of this reaction whkb does not differ from the preceding... 

When a mixture of methanol and methyl acrylate was heated in the presence of DBU, methyl 3-methoxypropionate was obtained in 95% yield (85EUP136851). In the absence of DBU, the addition reaction did not occur. 

Methoxypropionic acid, A1.8 Lactic acid, methyl ester, A1.9 C4H8O4... 

Methyl 3-methoxypropionate Oleylamine ethoxylate Esters, Carboxylic, Lactones / f z-Butyrolactone gamma- Butyrolactone / f z-Propiolactone... 

S5mthesis of (R)-amides using CAL-B as biocatalyst, octanethiol as radical racemization agent, and methyl-p-methoxypropionate as acyl donor at38-40 °C in MTBE [250]. 

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