Electrochemical Oxidation of 3-Aryl-2-cyanothioacrylamides

Abstract

Electrochemical oxidation of (Е)-3-aryl-2-cyanoprop-2-enethioamides in a undivided cell in the presence of KBr in an aqueous or aqueous-organic medium has led to the formation of (2Е,2′E)-2,2′-(1,2,4-thiadiazole-3,5-diyl)bis[3-arylacrylonitriles] in 37–76% yield. A plausible reaction mechanism has been discussed. In laboratory experiments, (2E,2′E)-2,2′-(1,2,4-thiadiazol-3,5-diyl)bis[3-(4-methoxyphenyl)acrylonitrile] has revealed pronounced antidote effect against herbicide 2,4-D on sunflower seedlings and no pronounced growth-regulating properties.