2-Methylpyridine → HCID 60077773, compound

Temperature

-40 °C

The reaction was carried out under argon in flame dried apparatus. n-BuLi (1.6 M in hexanes, 11.3 mL, 18.1 mmol) was added dropwise to a cooled (−40° C.) solution of 2-picoline (1.64 mL, 16.6 mmol) in THF (30 mL). When addition was complete the solution was stirred at −40° C. for 1 hour before cooling to −78° C. A solution of 2(S)-tert-butoxycarbonylamino-3,3-dimethyl-butyric acid pentafluorophenyl ester (3.00 g, 7.6 mmol) in THF (30 mL) was added via a cannula, maintaining the reaction temperature below −65° C. After stirring for 1 hour at −78° C. saturated NH4Cl solution (10 mL) was added and the reaction mixture was allowed to warm to room temperature before it was partitioned between EtOAc (200 mL) and saturated NH4Cl solution (200 mL). The organic extract was washed with water (200 mL) and brine (200 mL), dried over MgSO4 and concentrated in vacuo. The residue was purified by column chromatography (SiO2, 25% Et2O in hexanes) to give the title product as a bright yellow solid (1.01 g, 44%).

1. temperaturein flame
2. customdried apparatus
3. additionWhen addition
4. temperaturebefore cooling to −78° C
5. temperaturemaintaining the reaction temperature below −65° C
6. additionwas added
7. temperatureto warm to room temperature before it
8. customwas partitioned between EtOAc (200 mL) and saturated NH4Cl solution (200 mL)
9. extractionThe organic extract
10. washwas washed with water (200 mL) and brine (200 mL)
11. dry with materialdried over MgSO4
12. concentrationconcentrated in vacuo
13. customThe residue was purified by column chromatography (SiO2, 25% Et2O in hexanes)

ORD record

ord-66bb9f2e37e740f5bfddd5ac84759af1

Source dataset

uspto-grants-2004_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06716878B1