反应详情

Hydralazine free base (1 part by weight) was heated in 6 to 7 parts by volume of 15% hydrochloric acid to a temperature of 70-80° C. The solution was filtered hot to remove traces of insoluble materials that were undesired by-products of the preceding step. Ethanol (6 to 7 parts by volume) was added to the filtrate. As the resulting solution cooled to ambient temperature and then further to 3-8° C., an off-white to pale yellow precipitate of the desired product, hydralazine hydrochloride, was obtained. Typical yields were 80-90%.

1. filtrationThe solution was filtered hot
2. customto remove traces of insoluble materials that
3. additionEthanol (6 to 7 parts by volume) was added to the filtrate