Hydrochloric Acid → p-hydroxy-N-(2-hydroxyethyl)cinnamamide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

43.6 g (194 mmol) of p-acetoxycinnamoyl chloride was added to 200 ml of methylene chloride and heated at 40° C. to make a homogeneous solution. The solution was cooled down to 15°-20° C., into which 35.5 g (582 mmol) of monoethanolamine was dropped. Since the system generated heat during-the dropping, it was cooled and the dropping rate was so controlled that the liquid temperature was maintained at 15°-20° C. After completion of the dropping, the system was stirred at room temperature for 1 hour, and was then heated under reflux and stirred for further 1 hour to complete the reaction. After distillation of the methylene chloride under reduced pressure, 50 ml of ethanol was added so as to obtain a substantially homogeneous solution. Thereafter, 30.1 g (388 mmol) of a 40% methylamine aqueous solution was added to the system at one time, followed by heating to 40°-50° C. and stirring for 1 hour. The reaction solution was poured into 800 ml of water, to which a 12% hydrochloric acid aqueous solution was added to a pH of about 3. The resultant crystals were filtered off and recrystallized from acetone to obtain 24.9 g of p-hydroxy-N-(2-hydroxyethyl)cinnamamide as colorless or slightly yellow crystals.

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