Chlorotrimethylsilane → [4-Chloro-2-fluoro-3-(trifluoromethyl)phenyl](trimethyl)silane

Temperature

-70 °C

1-Chloro-3-fluoro-2-(trifluoromethyl)benzene (10 g, 50 mmol) was dissolved in tetrahydrofuran (100 ml), cooled to −70° C. under argon, and treated with a 1.4M solution of sec-butyl lithium in cyclohexane (37.5 ml, 52.5 mmol). Stirring was continued for 2 hrs and then trimethylsilyl chloride (6.7 ml, 52.5 mmol) was added and stirring continued, still at −70° C., for a further 1 hr. The mixture was allowed to warm to room temperature and the tetrahydrofuran was then removed in vacuo. The residue was partitioned between diethyl ether and water and then the organic layer was separated and washed with 2N aqueous hydrogen chloride. The organic phase was separated and concentrated to give the crude product which was purified by flash silica-gel column chromatography, eluting with hexane, to give pure [4-chloro-2-fluoro-3-(trifluoromethyl)phenyl](trimethyl)silane as a clear oil (10.35 g).

1. stirringstirring
2. waitcontinued, still at −70° C., for a further 1 hr
3. temperatureto warm to room temperature
4. customthe tetrahydrofuran was then removed in vacuo
5. customThe residue was partitioned between diethyl ether and water
6. customthe organic layer was separated
7. washwashed with 2N aqueous hydrogen chloride
8. customThe organic phase was separated
9. concentrationconcentrated
10. customto give the crude product which
11. customwas purified by flash silica-gel column chromatography
12. washeluting with hexane

ORD record

ord-483e182e59d54c8b89fb25fcc7d09f07

Source dataset

uspto-grants-2011_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08048907B2