Chlorotrimethylsilane → 2,6-Dichloro-4-trifluoromethyl-3-trimethylsilanylpyridine

Temperature

-20 °C

A dry 100 mL 3 neck rb flask was charged with diisopropylamine (2.15 mL, 15.3 mmol) and 40 mL of anhydrous THF. Reaction mixture was cooled at −20° C. under N2. A 2.5 M solution of n-BuLi in Hexane (5.90 mL, 14.8 mmol) was added dropwise via a syringe. The resulting reaction mixture was then cooled at −78° C. A solution of 2,6-dichloro-4-trifluoromethylpyridine (3.0 g, 14 mmol) in 5 mL of anhydrous THF was added slowly via an addition funnel to give a pale yellow solution. Reaction mixture stirred at −78° C. for 2 h. After which time, a solution of TMSCl (2.0 mL, 15.8 mmol) in 5 mL of THF was added dropwise via an addition funnel. The resulting reaction mixture was allowed to slowly warm up to room temperature and stirred over night. Reaction mixture was added to 150 mL of Et2O, washed with dilute HCl, then washed with aq. NaHCO3, dried over MgSO4, filtered and concentrated to give 3.80 g (95%) of 2,6-dichloro-4-trifluoromethyl-3-trimethylsilanylpyridine (Compound 8) as a brown oil:

1. customReaction mixture
2. customThe resulting reaction mixture
3. temperaturewas then cooled at −78° C
4. customto give a pale yellow solution
5. customReaction mixture
6. customThe resulting reaction mixture
7. temperatureto slowly warm up to room temperature
8. stirringstirred over night
9. customReaction mixture
10. washwashed with dilute HCl
11. washwashed with aq. NaHCO3
12. dry with materialdried over MgSO4
13. filtrationfiltered
14. concentrationconcentrated

ORD record

ord-f617d4d100ea404caa25513877429b1c

Source dataset

uspto-grants-2015_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09131694B2