Lithium Hydroxide → 4-(3-Bromophenoxy)butanoic acid

Temperature

50 °C

To a solution of ethyl 4-(3-bromophenoxy)butanoate (Preparation 55A, 3.3 g, 11.5 mmol) in THF (5 mL) was added lithium hydroxide (0.550 g, 23.0 mmol) dissolved in water (5 mL) at room temperature. The reaction mixture was heated at 50° C. for 3 h. The reaction mixture was concentrated and partitioned between ethyl acetate (50 mL) and 1N aqueous hydrochloric acid (20 mL) (pH of aqueous layer ˜3). The organic layer was washed with brine (20 mL), dried over sodium sulfate, and concentrated under reduced pressure to yield 4-(3-bromophenoxy)butanoic acid (2.9 g, 11.2 mmol, 97% yield) as an oil. 1H NMR (400 MHz, CDCl3) δ ppm 2.10-2.15 (m, 2H), 2.59 (t, J=7.26 Hz, 2H), 4.01 (t, J=6.05 Hz, 2H), 6.82 (ddd, J=8.14, 2.42, 1.10 Hz, 1H), 7.04-7.06 (m, 1H), 7.07-7.10 (m, 1H), and 7.14 (t, J=8.03 Hz, 1H).

1. concentrationThe reaction mixture was concentrated
2. custompartitioned between ethyl acetate (50 mL) and 1N aqueous hydrochloric acid (20 mL) (pH of aqueous layer ˜3)
3. washThe organic layer was washed with brine (20 mL)
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated under reduced pressure

ORD record

ord-d62ebff4eb6d4955b35ff2d6782cdda6

Source dataset

uspto-grants-2015_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09216972B2