N-bromobutanimide → HCID 59282949, compound

Temperature

110 °C

Tetrakis(triphenylphosphine) palladium(0) (0.439 g, 0.380 mmol) was added to a solution containing 2-chloro-4-fluoropyridine (1 g, 7.60 mmol) and tributyl(1-ethoxyvinyl)tin (2.59 ml, 7.60 mmol) in Toluene (15.21 ml). In a capped vial, the reaction was heated to 110° C. for overnight. LC/MS verified that the vinyl enolate intermediate formed. The reaction was cooled to room temperature, filtered thru a plug of Celite and the filtrate concentrated. The resulting residue was diluted with THF (20 mL) and water (2 mL). The reaction mixture was cooled to 0° C. and N-bromosuccinimide (1.624 g, 9.12 mmol) was added. The reaction was stirring for 1 hour and warmed to room temperature. The reaction was diluted with ethyl acetate and washed with water. Separated organics, dried with MgSO4, filtered and concentrated. Purified using Combiflash using 0% to 20% ethyl acetate in hexanes to afford 2-bromo-1-(4-fluoropyridin-2-yl)ethanone (1.4 g, 6.42 mmol, 84% yield) as a light purple oil. 1H NMR (CDCl3, 400 MHz), δ: 4.81 (s, 2H), 7.24 (m, 1H), 7.79 (m, 1H), 8.65 (m, 1H).

1. customformed
2. temperatureThe reaction was cooled to room temperature
3. filtrationfiltered
4. concentrationthe filtrate concentrated
5. additionThe resulting residue was diluted with THF (20 mL) and water (2 mL)
6. temperatureThe reaction mixture was cooled to 0° C.
7. temperaturewarmed to room temperature
8. washwashed with water
9. dry with materialSeparated organics, dried with MgSO4
10. filtrationfiltered
11. concentrationconcentrated
12. customPurified

ORD record

ord-d9407d2f729646d78c5c84981109adbb

Source dataset

uspto-grants-2013_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08420052B2