Synthesis and X-ray molecular structure of N-(1-amino-2,2-dichloroethyl)benzamides

Efficient procedures for the synthesis of N-(1-alkylamino-2,2-dichloroethyl)benzamides, N-(1-arylamino-2,2-dichloroethyl)benzamides and N-(1-amino-2,2-dichloroethyl)benzamides are reported. These compounds are of special interest as intermediates to access new heterocyclic series. N-(2,2-dichlorovinyl)amides react with primary or secondary alkylamines to yield the title compounds in high to quantitative yields. However, similar addition reactions with arylamines or ammonia are unsuccessful. In these cases the synthesis of the targeted products may be achieved by starting from N-(1,2,2,2-tetrachloroethyl)benzamides which are aminated via nucleophilic substitution yielding the corresponding N-(1-amino-2,2,2-trichloroethyl)benzamides. Finally, these compounds are selectively monodechlorinated by electrochemical reduction at constant cathodic potential. The crystallographic X-ray structure of N-(2,2-dichloro-1-isopentylaminoethyl)-4-methylbenzamide has been determined.