PROCEDE POUR PREPARER 2',6'-DIALKYL-N-(ALKOXYMETHYLE)2-CHLORACETANëLIDES

摘要

The invention relates to an improved method for the preparation of a 2',6'-dialkyl-N-alkoxymethyl-2-chloro-acetanilide compound of the general formula (I), (I) wherein R1, R2 and R3 are identical or different and stand for straight-chained or branched C1-4 alkyl groups. According to the invention a dialkyl aniline of the general formula (II), (II) wherein R1 and R2 are as defined above, is treated with aqueous formaldehyde solution in an apolar solvent at a temperature of 30 DEG to 80 DEG C., the solution of the resulting oxymethyl derivative formed with said apolar solvent is separated from the aqueous formaldehyde solution at an elevated temperature and then dehydrated, the resulting azomethine derivative is reacted with chloroacetyl chloride in the same apolar solvent medium, the resulting chloromethyl compound is reacted with an alcohol of the general formula (V), R3-OH (V) wherein R3 is as defined above, in an amount sufficient to bind the hydrochloric acid liberated in the reaction, the reaction mixture is admixed with water, and the organic phase containing the required end-product is separated and optionally processed.