One‐Pot Synthesis of 3‐Aryl‐5‐amino‐1,2,4‐thiadiazoles from Imidates and Thioureas by I2‐Mediated Oxidative Construction of the N–S Bond

A simple and practical method for the one‐pot synthesis of 3‐aryl‐5‐amino‐1,2,4‐thiadiazoles from imidates and thioureas has been developed. The protocol proceeds through sequential base‐mediated nucleophilic addition‐elimination reactions and an I2‐mediated oxidative coupling for the N–S bond formation. The approach employes readily available and nontoxic substrates and a simple workup to provide 3‐aryl‐5‐amino‐1,2,4‐thiadiazoles that have a free or substituted amino group.