反应详情

温度

-78 °C

To 4-bromo-3,5-dimethylanisole (a compound of Formula 5 from Example 3) (20 g, 93.0 mmol) in 500 mL of THF at -78° C. was added 120 mL of tert-Butyllithium (1.7 M in pentane). The reaction mixture was stirred for 30 minutes at -78° C. and then DMF (136.0 g, 186.0 mmol) was added. The reaction mixture was stirred for 1 hour at -78° C. and for 1.5 hours at room temperature, diluted with 300 mL of ether, washed with 300 mL of water, acidified 1N HC1, and 5×100 mL of brine. The organic portion was dried (MgSO4), filtered, and evaporated to give the crude product, which was purified by flash column chromatography (silica gel, 90:10 hexane/ethylacetate) to yield 2,6-dimethyl-4-methoxybenzaldehyde (a compound of Formula 6), (9.50 g, 57.8 mmol, 62%) as a white solid; 1HNMR (CDCl3 δ2.61 (s, 6H), 3.83 (s, 3H), 6.6 (s, 2H), 10.5 (s, 1H).

1. stirringThe reaction mixture was stirred for 1 hour at -78° C. and for 1.5 hours at room temperature
2. washwashed with 300 mL of water
3. dry with materialThe organic portion was dried (MgSO4)
4. filtrationfiltered
5. customevaporated
6. customto give the crude product, which
7. customwas purified by flash column chromatography (silica gel, 90:10 hexane/ethylacetate)