Various N-(1-aryl-1-alkenyl)-2-chloroacetamides bearing alkoxymethyl or alkylthiomethyl group on amide nitrogen were synthesized by a one-step hydroamidation of 2-aza-1,3-pentadienes. Some N-(1-aryl-1-alkenyl)-2-chloroacetamides were found to have high herbicidal activities against upland farm weeds.
2-Aza-1,3-butadienes bearing alkoxyl substituent were obtained easily by the reaction of ketimines with orthoesters. The reaction proceeded smoothly by the addition of small amount of p-toluenesulfonic acid. When acetals were used in place of orthoesters, the corresponding 2-aza-1,3-butadienes were similarly prepared.