反应详情

温度

0 °C

2,3-Dimethoxytoluene (2 g, 13.1 mmol) was weighed in a flask and ether was added to the flask. N,N,N′,N′-tetramethylethylenediamine (422 mg, 3.6 mmol) was added to the solution. While stirring, the mixture was cooled down to 0° C. and n-Butyl lithium 1.6M in hexane (2.25 mL, 3.6 mmol) was added slowly over 20 minutes. The solution was stirred at 0° C. for 30 minutes after which the ice bath was removed. The solution became yellow during addition and after removal of the ice bath, a precipitate started forming. The reaction mixture was left stirring overnight at room temperature under nitrogen then cooled down again to 0° C. and DMF (1.23 mL, 15.9 mmol) was added. The homogeneous reaction mixture was stirred at this temperature for 1 hour. The solution was poured onto crushed ice and 15 mL ammonium chloride 1N. The phases were separated and the organic phase was washed with 4 portions of 1N ammonium chloride. The organics were dried over sodium sulphate, filtered and the filtrate was evaporated under vacuum. The crude product was purified on normal silica with DCM to yield 1.27 g (58%) of 14 which was used in the next stage.

1. customwas removed
2. additionThe solution became yellow during addition
3. customafter removal of the ice bath
4. customa precipitate started forming
5. waitThe reaction mixture was left
6. stirringstirring overnight at room temperature under nitrogen
7. temperaturethen cooled down again to 0° C.
8. stirringThe homogeneous reaction mixture was stirred at this temperature for 1 hour
9. additionThe solution was poured
10. customThe phases were separated
11. washthe organic phase was washed with 4 portions of 1N ammonium chloride
12. dry with materialThe organics were dried over sodium sulphate
13. filtrationfiltered
14. customthe filtrate was evaporated under vacuum
15. customThe crude product was purified on normal silica with DCM