反应详情

温度

-60 °C

To a solution of the product of Step 1 (112 g, 0.46 mol) in THF (1500 ml) at −60° C. under argon, was added n-BuLi (325 ml, 0.52 mol) over 1 hour. After stirring at −60° C. for 1 hour a solution of DMF (39.7 ml) in THF (50 ml) was added dropwise over 1 hour. The reaction was stirred at −60° C. for 1 hour before being allowed to warm to room temperature. After 1 hour the reaction was quenched with saturated aqueous sodium hydrogen carbonate solution and extracted into ethyl acetate. The organic phase was then dried (sodium sulphate), concentrated in vacuo and the residue purified by silica gel chromatography, to give the title compound (57 g, 65%) as a yellow solid; 1H NMR (CDCl3) 10.0 (1H, s), 7.83–7.73 (3H, m), 4.02 (3H, s), 3.10 (2H, m), 2.92 (2H, m).

1. additionwas added dropwise over 1 hour
2. temperatureto warm to room temperature
3. customAfter 1 hour the reaction was quenched with saturated aqueous sodium hydrogen carbonate solution
4. extractionextracted into ethyl acetate
5. dry with materialThe organic phase was then dried (sodium sulphate)
6. concentrationconcentrated in vacuo
7. customthe residue purified by silica gel chromatography