Preparation of 2-cyano-3,3-bis(methylthio)acrylamide: A mixture of cyanoacetamide (10 g, 118.9 mmol) and potassium hydroxide (6.661 g, 118.9 mmol) in acetonitrile (100 mL) was stirred for 1 hour at room temperature. Subsequently, carbon disulfide (9.054 g, 118.9 mmol) was slowly added at the same temperature and stirring was continued for 3 hours. Next, dimethyl sulfate (19.5 g, 154.6 mmol) was added and the reaction mixture was stirred at room temperature overnight. Upon completion of the reaction, the volatiles were removed under vacuum and the residue was redissolved in ethyl acetate, washed sequentially with water and brine, dried over anhydrous magnesium sulfate, and subsequently concentrated under vacuum. The resulting solid was ground with a solvent mixture of ethyl acetate/hexane, filtered and dried to afford the target compound 2-cyano-3,3-bis(methylthio)acrylamide (9.4 g, 42% yield, 99.0% purity) as a yellow solid.
