(Trifluoromethyl)trimethylsilane → 1-(5-Bromopyridin-2-yl)-2,2,2-trifluoroethan-1-ol

Temperatur

0 °C

To a cooled, stirred solution of 5-bromopyridine-2-carbaldehyde (3.72 g, CAS 31181-90-5) and (trifluoromethyl)trimethylsilane (3.56 ml) in THF (30 ml) at 0° C. was added dropwise tetrabutylammonium fluoride solution (1.0 ml, 1 M solution in THF). The reaction mixture was stirred at 0° C. for 30 min and then at room temperature for 2 hours. The mixture was then diluted with 1 N aq. HCl (20 ml) and stirring was continued for a further 2 hours. The mixture was diluted with water and extracted twice with ethyl acetate. The combined organic phases were dried over sodium sulfate and concentrated in vacuo. The residue was purified by column chromatography (SiO2; gradient: heptane/EtOAc) to give (RS)-1-(5-bromo-pyridin-2-yl)-2,2,2-trifluoro-ethanol as a light yellow solid (3.35 g, 65%). MS (ISP): 258.0 ([{81Br}M+H]+), 256.1 ([{79Br}M+H]+).

1. waitat room temperature for 2 hours
2. stirringstirring
3. waitwas continued for a further 2 hours
4. extractionextracted twice with ethyl acetate
5. dry with materialThe combined organic phases were dried over sodium sulfate
6. concentrationconcentrated in vacuo
7. customThe residue was purified by column chromatography (SiO2; gradient: heptane/EtOAc)

ORD-Eintrag

ord-88da8c195d5d408e8d933d12e35175a6

Quelldatensatz

uspto-grants-2014_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08802673B2