Preparation method of 3-guanidino propanoic acid

Abstract

The invention relates to a preparation method of 3-guanidino propanoic acid. The preparation method comprises the following steps of: adding 3-aminopropionic acid to methanol, thereby obtaining a solution a at 15 DEG C; putting monocyanamide into methanol, thereby obtaining a solution b; feeding the solution b to the solution a, thereby obtaining a solution c at a temperature within 15 DEG C and PH in the range from 7.5 to 8.0; performing vacuum concentration on the solution c and filtering at -5 DEG C, thereby obtaining a crude product of sodium 3-guanidine propionate; preparing the crude product into an aqueous solution of sodium 3-guanidine propionate, thereby obtaining a solution d2; filling H type weakly acidic cation exchange resin into an ion exchange column, and feeding the solution d2 into the ion exchange column and detecting no 3-guanidino propanoic acid; blending the exchange solution collected by the step e and performing decompression concentration on the exchange solution, feeding methanol, reducing the temperature to -10 DEG C for crystallization, thereby obtaining a crystalline mixed liquid f; and then filtering and drying the crystalline mixed liquid f to obtain 3-guanidino propanoic acid. The problem of removing sodium ions during the production of 3-guanidino propanoic acid is solved through exchange treatment of the weakly acidic cation exchange resin; as methanol is taken as a solvent, the utilization and recovery cost of the solvent is lower and the preparation method is safer to operate; side-reactions are few; the 3-guanidino propanoic acid is extracted by ion resin exchange; and the yield of the 3-guanidino propanoic acid is 76.0% and the purity of the 3-guanidino propanoic acid is 99.0%.

Description

field of invention [0001] The invention relates to a compound used as a food additive and a pharmaceutical intermediate, in particular to a preparation method of 3-guanidinopropionic acid, which belongs to the technical field of chemical industry. Background technique [0002] For a long time, guanidine compounds have been widely used in the fields of medicine, pesticides and chemicals as bactericides, catalysts, nutrients, feed and cosmetic additives. Creatine and its derivatives, guanidinoacetic acid, guanidinopropionic acid and other guanidino compounds with 2-3 carbon atoms are widely used. 3-Guanidinopropionic acid can be used in food additives, surfactants in cosmetics, feed additives, nutritional fortifiers, beverage additives, pharmaceutical raw materials, etc. Due to the active characteristics of guanidine compounds, the yield of 3-guanidinopropionic acid is low in the production process, and the extraction process is difficult, which seriously restricts the large-...

AI Technical Summary

Problems solved by technology

Due to the active characteristics of guanidine compounds, the yield of 3-guanidinopropionic acid is low in the production process, and the extraction process is difficult, which seriously restricts the large-scale production of products

The document whose application number is 201110210823.3 discloses a chemical synthesis method of guanidinopropionic acid, adding isopropanol, 3-aminopropionic acid and 10% sodium hydroxide solution in a reaction kettle, stirring and dissolving at room temperature, and obtaining an alkaline mixed solution; add cyanamide solution dropwise to the alkaline mixed solution, then stir and reflux at a certain temperature for a period of time, after the reaction is completed, concentrate under reduced pressure, evaporate the solvent to obtain the crude product of guanidinopropionic acid; put guanidinopropionic acid into the reaction kettle Crude propionic acid, water and isopropanol are stirred for a period of time at room temperature, then suction filtered, rinsed, and dried to obtain guanidinopropionic acid with an unsatisfactory yield