反应详情

A solution of 119.1 g. (0.407 mol) ethyl 2-[4-(2-acetaminoethyl)-phenoxy]-2-methylpropionate in 750 ml. ethanol is mixed with a solution of 224.4 g. (4.00 mol) potassium hydroxide in 800 ml. water and heated under reflux for 8 hours. While cooling, there are then added exactly 4.00 mol hydrogen chloride (for example, in the form of 2 N hydrochloric acid), cooling is intensified and, after some time, the crystals which separate out are filtered off with suction. These are washed with water and dried; there are obtained 48.4 g. of product (53% of theory) which melts, with decomposition, at 274° C. From the mother liquor there are obtained, after distilling off the ethanol and cooling, a further 32.5 g. (36% of theory) of product with a melting point of 263°-270° C. The crude 2-[4-(2-aminoethyl)-phenoxy]-2-methylpropionic acid obtained is recrystallised from ethanol and water (4:1 v/v) and then has a melting point of 284° C. The corresponding hydrochloride has a melting point of 187°-189° C.

1. temperatureunder reflux for 8 hours
2. temperatureWhile cooling
3. customafter some time, the crystals which separate out
4. filtrationare filtered off with suction
5. washThese are washed with water
6. customdried
7. customthere are obtained 48.4 g
8. custommelts, with decomposition, at 274° C
9. customFrom the mother liquor there are obtained
10. distillationafter distilling off the ethanol
11. temperaturecooling