10.1016/j.tetlet.2009.03.017
The research focuses on the efficient synthesis of cyanamide from amine, utilizing a hypervalent iodine(III) reagent, specifically diacetoxyiodobenzene (DIB), as a non-metallic, non-toxic, and eco-friendly desulfurizing agent. The purpose of this study was to develop an alternative method to the traditional synthesis of cyanamides, which often involves the use of highly toxic cyanogen halides or other harmful reagents. The researchers achieved this by employing a one-pot strategy that starts with dithiocarbamic acid salts/amines, generates alkyl or aryl isothiocyanates in situ through desulfurization with DIB, and then reacts these with aqueous ammonia to form alkyl or aryl thiourea. Further oxidative desulfurization with DIB leads to the formation of the corresponding cyanamide in good yields. The conclusions drawn from the study highlight the mild reaction conditions, shorter reaction times, and environmentally benign protocol as significant advantages, making this methodology a suitable alternative for the preparation of various organic cyanamides. The chemicals used in the process include dithiocarbamic acid salts, amines, aqueous ammonia, and DIB, with the latter serving as a key reagent for both desulfurization steps and the oxidation of thiourea to cyanamide.