Potassium Carbonate → (2-Bromopyridin-4-yl)acetic acid

Temperature

100 °C

A suspension of 2-(2-bromo-pyridin-4-yl)-malonic acid diethyl ester (115 g, 316 mmol) and K2CO3 (125.23 g, 907.5 mmol) in water (500 ml) was heated at 100° C. for 8 h under constant stirring. Reaction mixture was cooled to rt and concentrated under reduced pressure to remove solvent completely. The solid residue was dissolved in minimum quantity of water (25 ml) and washed with 20% ethyl acetate in hexane to remove non polar impurities. The aqueous layer was separated and cooled to 0° C. followed by adjusting pH to 7 using aq. 6 N HCl. The precipitated solid was filtered using Buchner funnel, washed with ice cold water and dried under vacuum to furnish title compound as an off white solid. with sufficient purity. Yield: 60.0 g (76.3%). TLC (70% ethyl acetate in hexane) Rf=0.05; LCMS: RtH8=0.193; [M+1]+=215.9 and 217.9; HPLC RtH9=3.025 min (98%); 1H NMR (400 MHz, CDCl3): b 12.71 (s, 1H), 8.33 (d, 1H), 7.61 (s, 1H), 7.37 (d, 1H), 3.71 (s, 3H).

1. customReaction mixture
2. temperaturewas cooled to rt
3. concentrationconcentrated under reduced pressure
4. customto remove solvent completely
5. dissolutionThe solid residue was dissolved in minimum quantity of water (25 ml)
6. washwashed with 20% ethyl acetate in hexane
7. customto remove non polar impurities
8. customThe aqueous layer was separated
9. temperaturecooled to 0° C.
10. filtrationThe precipitated solid was filtered
11. washwashed with ice cold water
12. customdried under vacuum

ORD record

ord-a5fdacc9655849898bd44a259b2ce383

Source dataset

uspto-grants-2014_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08865712B2