Synthesis of 5-(substituted phenyl) 4-acetyl-2-methylthio-Δ2-1,3,4-thiadiazolines and their oxidation with potassium permanganate

Abstract

The reaction of aldehyde methylthio (thiocarbonyl) hydrazones (2) with acetic anhydride or acetyl chloride gave 5-(substituted phenyl) 4-acetyl-2-methylthio-Δ²-1,3,4-thiadiazolines (3). Oxidation of compounds (3) with potassium permanganate in acetic acid furnished 5-aryl-2-methylsulphonyl-1,3,4-thiadiazoles (4), 4-acetyl-5-aryl-2-methylsulphonyl-Δ²-1,3,4-thiadiazolines (5), and 4-acetyl-5-aryl-2-methylsulphonyl-Δ²-1,3,4-thiadiazoline 1,1-dioxides (6).