反应详情

To a solution of 2-(4-bromo-2,6-dimethylphenyl)-3-methoxycyclopent-2-enone (5 g, 17 mmol) in anhydrous tetrahydrofuran (50 ml) under nitrogen atmosphere is added lithium bis(trimethylsilyl)amide (22.4 ml, 20 mmol, 0.9M solution in tetrahydrofuran) dropwise at −75°C. The resulting solution is stirred at this temperature for 40 minutes, then a second solution of pyridine-2-carboxaldehyde (2.18 g, 20 mmol) in anhydrous tetrahydrofuran (50 ml) is added over 20 minutes. The resulting solution is stirred at −75°C. for 2 hours, then allowed to warm to room temperature and stir for a further 2 hours. The reaction mixture is quenched with ice cold water (30 ml), extracted with ethyl acetate (3×100 ml), then dried over sodium sulfate, filtered and the filtrate is concentrated in vacuo to afford 2-(4-bromo-2,6-dimethylphenyl)-5-(hydroxypyridin-2-ylmethyl)-3-methoxycyclopent-2-enone. This material is used directly in the next step without further purification.

1. stirringThe resulting solution is stirred at −75°C. for 2 hours
2. stirringstir for a further 2 hours
3. customThe reaction mixture is quenched with ice cold water (30 ml)
4. extractionextracted with ethyl acetate (3×100 ml)
5. dry with materialdried over sodium sulfate
6. filtrationfiltered
7. concentrationthe filtrate is concentrated in vacuo