Processing method for producing intermediate 2-aminobutyric acid of levetiracetam

The invention provides a processing method for producing an intermediate 2-aminobutyric acid of levetiracetam, which solves the problems that the existing products have excessive impurity content or enterprises can not bear production cost, etc. The processing method is characterized by taking n-propanal as a raw material to react with ammonium bicarbonate and sodium cyanide to product heroin; hydrolyzing under a low-pressure alkaline condition to obtain 2-amino-sodium butylate; adjusting pH into an equivalent point with hydrochloric acid to obtain the 2-aminobutyric acid; and recrystallizing to remove a by-product-sodium chloride, and the content of the product exceeds 99%, thus meeting the use requirements of foreign customers, wherein the cost of production materials is a half of the costs of the additional two lines. The processing method can be widely applicable to industrial production of medium and small-sized enterprises.