Synthesis
To the reaction flask was added 1200 mL of ethanol and 111.3 g of benzaldehyde (1.05 mol), followed by 110 mL of 25% ammonia (1.60 mol), stirred for 15 min, then 92 g of 1-chloro-2,3-epoxypropane (1.00 mol) was slowly added, controlling the reaction temperature to be lower than 40°C. The reaction temperature was controlled to be below 40°C. After the addition was completed, the reaction was carried out at 35-40 °C for 8 h, followed by a continuation of the reaction for 15 h at room temperature. After confirming that 1-chloro-2,3-epoxypropane was almost completely consumed by gas chromatography monitoring, the reaction solution was concentrated. To the concentrate was added 800 mL of toluene, stirred at 35-40 °C, and 270 mL of 6N hydrochloric acid (1.62 mol) was added slowly and dropwise. After completion of the dropwise addition, the reaction was continued at this temperature for 6 hours. At the end of the reaction, the organic layer was washed with water, the aqueous layer was combined and concentrated to dryness. Anhydrous ethanol was added to the residue, concentrated again and finally toluene was added to azeotropically remove the water. The resulting residue was recrystallized with a solvent mixture of ethanol and ethyl acetate to give 108.1 g of a white solid, i.e., 3-chloro-2-hydroxypropylamine hydrochloride (Compound II); melting point: 127-130°C, molar yield: 74.04% (as 1-chloro-2,3-epoxypropane).
