53726-14-0Relevant articles and documents
Method for splitting aminobutanamide by using ammonium hydrogen tartrate
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Paragraph 0024; 0029-0031; 0036-0038; 0043-0044, (2021/06/09)
The present invention relates to the technical field of aminobutanamide resolution, and discloses a method for resolving aminobutanamide by using ammonium hydrogen tartrate, and the method comprises the following steps: taking 10-20 parts of ammonium tartrate, placing ammonium tartrate in a reaction flask, adding 20-40 parts of purified water, and performing stirring for 0.5-1.5 h to obtain an ammonium tartrate solution. According to the method for resolving aminobutanamide by using ammonium hydrogen tartrate, the ammonium hydrogen tartrate is used as a reactant and is subjected to resolution reaction with racemic 2-aminobutanamide, and an L-2-aminobutanamide ammonium hydrogen tartrate wet product obtained after the reaction is reacted with methanol and ammonia gas, so L-2-aminobutanamide and ammonium hydrogen tartrate can be separated out; the L-2-aminobutanamide liquid can be obtained, the ammonium hydrogen tartrate can be converted into the ammonium tartrate solid for recovery and storage, and the L-2-aminobutanamide solid can be used for splitting the aminobutanamide in the next ammonium hydrogen tartrate preparation so as to achieve the recovery and reutilization of the reactants, such that the production cost is reduced, and the low cost purpose is achieved.
Preparation method of L-2-aminobutanamide hydrochloride
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Paragraph 0020; 0026; 0029; 0035; 0038; 0044, (2021/06/21)
The invention relates to the technical field of preparation of chiral drug intermediates, and discloses a preparation method of L-2-aminobutanamide hydrochloride, which comprises the following steps: dropwise adding ethyl 2-bromobutyrate into stronger ammonia water, and carrying out chemical reaction in a closed container to prepare a prefabricated mixture; According to the preparation method of the L-2-aminobutanamide hydrochloride, ethyl 2-bromobutyrate is used as an initial raw material, and the medical intermediate L-2-aminobutanamide hydrochloride is prepared through ammonolysis and chiral resolution. Compared with the traditional preparation method, the preparation method adopts a chiral reagent (+)-mandelic acid with low raw material price and racemic 2-aminobutanamide hydrochloride to form diastereoisomers, the L-2-aminobutanamide hydrochloride is obtained through resolution by utilizing the difference of the dissolving properties of the diastereoisomers in ethanol, the optical purity and the chemical purity of the product are high, and the technical scheme has the advantages of mild reaction conditions, short reaction steps, high yield, stable product quality and easy realization of industrial production.
Preparation method of (S)-(+)-2-aminobutanamide hydrochloride
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Paragraph 0032; 0038-0043; 0049-0054; 0060-0065; 0071-0076, (2020/08/02)
The invention discloses a preparation method of (S)-(+)-2-aminobutanamide hydrochloride, and relates to a preparation method of a levetiracetam key intermediate, and the method comprises the followingspecific steps: carrying out esterification reaction on L-2-aminobutyric acid serving as a starting material and thionyl chloride, and concentrating part of solvent after the reaction is finished; introducing ammonia gas to neutralize generated hydrogen chloride and residual thionyl chloride; and filtering, introducing ammonia gas, and carrying out an ammonolysis reaction to obtain the (S)-2-aminobutanamide hydrochloride after the treating is finished. According to the preparation method, the starting material is simple and easy to obtain, the one-pot method is adopted, the atom utilization rate is high, operation is easy and convenient, and the obtained product quality is high.