反应详情

To a yellow solution of 2,2,6,6-TMPH (8.30 g, 58.88 mmol) in THF (9 mL) was added n-BuLi (25 mL) slowly at −78° C. under protection of nitrogen. Thereto, the mixture was warmed up to room temperature, stirred at this temperature for an hour, and then cooled to −78° C. again. A solution of 4-bromo-2-methylbenzoic acid (6.0 g, 28.04 mmol) in THF (60 mL) was added slowly, kept stirring at this temperature for an hour, added MeI (7.96 g, 56.07 mmol) solution (in 35 mL THF), the mixture above was then stirred overnight at room temperature. LCMS showed the reaction was completed. Water was added, the mixture was then washed with ethyl acetate. The aqueous phase was acidified to pH=1, extracted with ethyl acetate twice, and concentrated the organic phase to a residue which was trituated with PE/EA=1/1 to give 4.28 g of the title compound (67%).

1. temperaturecooled to −78° C. again
2. stirringkept stirring at this temperature for an hour
3. stirringthe mixture above was then stirred overnight at room temperature
4. washthe mixture was then washed with ethyl acetate
5. extractionextracted with ethyl acetate twice
6. concentrationconcentrated the organic phase to a residue which