2,2,6,6-Tetramethylpiperidine → HCID 90310765, compound

Temperature

-78 °C

To a 25 mL flask vial were added a stir-bar, 2.1 mL dry THF, and 2,2,6,6-tetramethylpiperidine (0.22 mL, 1.0 mmol). The flask was cooled to −78° Celsius and then treated with n-BuLi (0.48 mL, 1.9 mmol, 2.5 M in hexanes) over 2 minutes. The resultant mixture was stirred for 5 min and then warmed to 0° Celsius. After 30 min, the mixture was re-cooled to −78° Celsius and treated with B(O-iPr)3 (0.26 mL, 1.1 mmol) over 4 min. After 15 min, a solution consisting of tert-butyl(2-fluoro-6-methylphenoxy)dimethylsilane (247 mg, 1.03 mmol) in dry THF (2.1 mL) was added over the course of 6 min and stirring continued for 1 hour at −78° Celsius. The mixture was then warmed to rt, treated with HOAc (0.5 mL), and then poured into water (100 mL) and stirred for 5 min. The aqueous mixture was then extracted with EtOAc (3×100 mL), the combined extracts dried over Na2SO4, filtered, and concentrated to dryness to give the title compound, which was used directly in the next synthetic step.

1. additionTo a 25 mL flask vial were added a stir-bar
2. temperaturewarmed to 0° Celsius
3. temperaturethe mixture was re-cooled to −78° Celsius
4. waitAfter 15 min
5. additionwas added over the course of 6 min
6. waitcontinued for 1 hour at −78° Celsius
7. temperatureThe mixture was then warmed to rt
8. stirringstirred for 5 min
9. extractionThe aqueous mixture was then extracted with EtOAc (3×100 mL)
10. dry with materialthe combined extracts dried over Na2SO4
11. filtrationfiltered
12. concentrationconcentrated to dryness

ORD record

ord-d6440f84cad8495ab2bd4c7da5217999

Source dataset

uspto-grants-2015_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09073876B2