In a 250 mL round-bottomed flask equipped with a thermometer, a magnetic stirrer, and a constant-pressure dropping funnel, 4.80 g of thiourea is added, and to the constant-pressure dropping funnel are added 5 mL of hydrogen peroxide and .
50 mL of 3 mol/L hydrochloric acid was added. The flask was cooled in an ice-water bath to maintain the reaction temperature inside the flask, and the mixture of hydrogen peroxide and hydrochloric acid was added slowly and dropwise with vigorous stirring.
The reaction temperature was maintained at about 15 by controlling the rate of addition. After the addition of the reactants, a white precipitate was precipitated, stirring was continued, and the reaction was cooled in an ice bath (keeping the reaction temperature at about 3C) for 1.5 h. The reaction was stopped.
The reaction was stopped after 1.5 h. Add 200 mL of anhydrous ethanol and 60 mL of concentrated hydrochloric acid, until the dithiocarbamidine hydrochloride completely precipitated, filtration, washed with hot anhydrous ethanol, dried under vacuum at 85 for 3 h, yielding a white solid 4.34 h. The reaction was continued with stirring, and ice bath cooling (keep the reaction temperature at 3 ).
h, obtained white solid 4.34 g, yield 61.93%.
