左乙拉西坦的制备方法

The Synthesis Method of Levetiracetam

以S-2-氨基丁酰胺盐酸盐与4-氯丁酰氯为起始原料,二氯甲烷为溶剂,四丁基溴化铵为催化剂,经环合反应得粗品左乙拉西坦.加丙酮和纯净水回流后析晶、过滤得左乙拉西坦成品,合成过程中不含特殊的反应条件,收率55%~60%.该方法合成步骤少,工艺简单,原料易得,产品质量可控,工艺稳定可靠,适合工业化生产.

Crude levetiracetam was obtained via cyclization reaction using S-2-aminobutanamide hydrochloride and 4-chloroprene chloride as the starting material,methylene chloride as solvent and tetrabutylammonium bromide as a catalyst.After acetone and pure water reflux,the levetiracetam products was obtained by crystallization and filtration.The synthesis process did not need special reaction conditions.The yield was 55%to 60%.The method has the advantages of less synthetic steps,simple process,easily obtainable raw materials,controllable product quality,stable and reliable process and suitability for industrial production.