Process for the production of n-(2,6-dimethyl-phenyl)-2-piperazin-1-yl-acetamide

Abstract

The present invention relates to a novel process, suitable for industrial exploitation for the production of N-(2,6-dimethyl-phenyl)-2-piperazin-1-yl-acetamide, also known as N-lidocaine, obtained from the reaction of piperazine with N-haloacetyl-2,6-xylidine. The process comprises the consecutive steps a) through f) a) reacting piperazine with N-haloacetyl-2,6-xylidine in a molar ratio between about 1/1 and about 6/1 in an aqueous solvent in which has been dissolved an equimolar amount of HCl; b) separating the solid formed in step a) from the reaction mixture; c) neutralizing the filtrate; d) extracting the filtrate with a solvent which is not or only to a small extent miscible with the aqueous solvent mentioned in step a); e) crystallizing the N-(2,6-dimethyl-phenyl)-2-piperazin-1-yl-acetamide from the solvent mentioned in step d) and f) separating the solid obtained in step e) from the solvent mentioned in step d).

Dependencies are inferred from the claim text.