Acetone → HCID 86668029, compound

Temperature

-78 °C

To a solution of 2-bromo-5-fluoropyridine (25 g, 142 mmol) in diethylether (600 ml) was slowly added n-butyllithium (2.5 M in hexane, 56.8 ml, 142 mmol) at −78° C. under a nitrogen atmosphere. The resulting yellow reaction mixture was stirred at −78° C. for 2 hours and dry acetone (11.47 ml, 156 mmol) was added over 30 minutes. Stirring was continued at −78° C. for 1 hour. HCl (2N, 50 ml) was added and the reaction mixture was warmed to 0° C. The pH of the mixture was adjusted to ˜7 with 2N HCl solution. The reaction mixture was diluted with ethyl acetate and washed with brine, dried over sodium sulfate, filtered and concentrated in vacuo. The crude product (29.36 g) was chromatographed over silica gel (cyclohexane:ethyl acetate 9:1): 22.3 g (67.1% yield). TLC (cyclohexane/ethyl acetate 9:1) Rf=0.33; LCMS RtH5=0.89 min (ES+ 234, 236). 1H-NMR (360 MHz, DMSO-d6): 7.72-7.62 (m, 2H), 5.27 (s, 1H, OH), 1.50 (s, 6H, 2×CH3).

1. customat −78° C.
2. stirringStirring
3. waitwas continued at −78° C. for 1 hour
4. temperaturethe reaction mixture was warmed to 0° C
5. washwashed with brine
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe crude product (29.36 g) was chromatographed over silica gel (cyclohexane:ethyl acetate 9:1)
10. customLCMS RtH5=0.89 min (ES+ 234, 236)

ORD record

ord-f233a9cc641642a0b5f8738de22a9e7c

Source dataset

uspto-grants-2014_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08637508B2