2,2,6,6-Tetramethylpiperidine → HCID 90310803, compound

Temperature

-78 °C

To a 500 mL round-bottom flask were added a stir bar, dry THF (83 mL) and 2,2,6,6-tetramethylpiperidine (11 mL, 65 mmol). The flask was cooled to −78° C. (bath temp) and then treated with 2.5 M n-BuLi in hexanes (25 mL, 62.5 mmol) over 2 min. The resultant mixture was stirred for 5 min and then allowed to warm to 0° C. After 35 min, the mixture was re-cooled to −78° Celsius and treated with B(O-iPr)3 (14 mL, 60 mmol) over 4 min. After 16 min, a solution consisting of 1-cyclobutyl-3-fluoro-2-methoxybenzene (10.0 g, 55.6 mmol) and dry THF (27 mL) was added over the course of 6 min and stirring continued for 3.5 hours before adding saturated NH4Cl (200 mL). The mixture was then poured into water and stirred for 5 min. The aqueous mixture was then extracted with EtOAc (200 mL×3), the combined extracts dried over MgSO4, filtered and concentrated to dryness to give the crude product as an off-white solid. The crude product was subjected to FCC to give the title compound (7.21 g). 1HNMR (400 MHz, CD3OD): δ 7.11-7.07 (m, 2H), 3.38 (s, 3H), 3.82-3.80 (m, 1H), 2.37-2.33 (m, 2H), 2.19-2.11 (m, 3H), 2.09-1.90 (m, 1H).

1. additionTo a 500 mL round-bottom flask were added a stir bar
2. temperatureto warm to 0° C
3. temperaturethe mixture was re-cooled to −78° Celsius
4. waitAfter 16 min
5. additionwas added over the course of 6 min
6. waitcontinued for 3.5 hours
7. stirringstirred for 5 min
8. extractionThe aqueous mixture was then extracted with EtOAc (200 mL×3)
9. dry with materialthe combined extracts dried over MgSO4
10. filtrationfiltered
11. concentrationconcentrated to dryness
12. customto give the crude product as an off-white solid

ORD record

ord-dbca0cffb9b44c78808c29f7e6c361cb

Source dataset

uspto-grants-2015_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09073876B2