Methanol → Methyl 4-aminobenzenebutanoate

Temperature

60 °C

A 250-mL round bottom flask was charged with 4-(4-aminophenyl)butyric acid (2.00 g, 11.2 mmol) in methanol (50 mL) and treated with conc. sulfuric acid (1 mL). The resultant mixture was heated to reflux for 1.5 h. After this time, methanol (˜25 mL) was distilled off. The reaction was cooled to 60° C. and methyl tert-butyl ether was added. The mixture was allowed to slowly cool to room temperature, then diluted with hexanes (50 mL) to afford a white solid. The solid was dissolved in THF (6 mL)/water (4 mL) and treated with conc. NH4OH (6 mL). The mixture was diluted with dichloromethane (50 mL) and the layers separated. The organic layer was washed with saturated sodium chloride (5 mL), dried over sodium sulfate, filtered and concentrated under reduced pressure to afford the title compound (2.07 g, 96%) as a brown solid. MW=193.24. 1H NMR (DMSO-d6, 500 MHz) δ 6.83-6.79 (m, 2H), 6.50-6.46 (m, 2H), 4.81 (s, 2H), 3.57 (s, 3H), 2.39 (t, J=7.5 Hz, 2H), 2.25 (t, J=7.5 Hz, 2H), 1.73 (quin, J=7.5 Hz, 2H).

1. temperatureto reflux for 1.5 h
2. distillationAfter this time, methanol (˜25 mL) was distilled off
3. additionmethyl tert-butyl ether was added
4. temperatureto slowly cool to room temperature
5. additiondiluted with hexanes (50 mL)
6. customto afford a white solid
7. customthe layers separated
8. washThe organic layer was washed with saturated sodium chloride (5 mL)
9. dry with materialdried over sodium sulfate
10. filtrationfiltered
11. concentrationconcentrated under reduced pressure

ORD record

ord-7acfb7e839a74b0d9ed7da887b963f5d

Source dataset

uspto-grants-2015_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09221843B2