Abstract: A process for the preparation of N-[3-[3-(dimethylamino)-1-oxo-2-propenyl]phenyl]-N-ethyl acetamide of formula II, comprising reacting a compound N-[3-[3-(dimethylamino)-1-oxo-2-propenyl]phenyl]acetamide of formula III, with an ethylating agent in the presence of a strong alkali metal hydroxide and a phase transfer catalyst in a polar-aprotic solvent, and a process for preparation of Zaleplon, which is substantially free of impurities using the said compound of formula II.

Abstract: A process for producing gabapentin, (1-(aminomethyl)-1-cyclohexaneacetic acid) from gabapentin hydrochloride salt. In the disclosed process, the gabapentin hydrochloride is converted to gabapentin using an inorganic base, such as barium hydroxide. Gabapentin hydrochloride is converted to gabapentin sulfate which in turn is converted to free base using barium hydroxide. The process is directed to improvement in the manufacture of gabapentin which would be industrially feasible and effective. Gabapentin obtained following the process of the invention is suitable as a drug especially in the treatment of cerebral diseases such as epilepsy.