Boron trifluoride etherate → p-Aminophenylacetic acid ethyl ester

A solution of 8.2 g. of 4-aminophenylacetic acid, 150 ml. of absolute ethanol, and 3 ml. of boron trifluoride etherate is heated to reflux for 15 hours. The solution is concentrated by distillation and then evaporated to dryness in vacuo. The residue is dissolved in ethyl ether, washed with aqueous sodium bicarbonate, dried, and evaporated to yield ethyl 4-aminophenylacetate. A mixture of 5.0 g. of this amine, 9.7 g. of 14-(trimethylsilyl)tetradecyl bromide, 4.2 g. of anhydrous potassium carbonate and 40 ml. of hexamethylphosphoramide is heated at 80° C. for 7 hours. The mixture is then cooled, diluted with water, and extracted with ethyl ether. The ether extracts are washed with water, dried and evaporated. The residue is recrystallized yielding ethyl 4-[14-(trimethylsilyl)tetradecylamino]phenylacetate. A mixture of 6.0 g. of this ester, 7.0 g. of potassium hydroxide and 100 ml. of ethanol-water is heated to reflux for 4 hours. While hot, the mixture is adjusted to pH 7 with concentrated hydrochloric acid.. The mixture is diluted with water, cooled and filtered. Recrystallization of the precipitate yields the title product as a white solid.

1. temperatureto reflux for 15 hours
2. concentrationThe solution is concentrated by distillation
3. customevaporated to dryness in vacuo
4. dissolutionThe residue is dissolved in ethyl ether
5. washwashed with aqueous sodium bicarbonate
6. customdried
7. customevaporated

ORD record

ord-5abca2d8d92043738de3da117c428ef0

Source dataset

uspto-grants-1987_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04670421