反应详情

To a suspension of sodium hydride (7.8 g, 200 mmol) in tetrahydrofuran (100 mL) under nitrogen was added dropwise a solution of tert-butyl methyl malonate (20 mL, 120 mmol) in anhydrous tetrahydrofuran (100 mL) via syringe. The reaction mixture was stirred for 0.5 h before a solution of the intermediate prepared in Step D above (20.1 g, 97.6 mmol) in tetrahydrofuran (200 mL) was added slowly via syringe. The reaction was stirred at room temperature overnight, then quenched with a saturated solution of ammonium chloride. The organic layer was separated and the aqueous layer was extracted with three portions of ethyl acetate. The combined organic layers were washed with water, dried over sodium sulfate and concentrated in vacuo. Flash chromatography afforded the title compound. 1H NMR (500 MHz, CDCl3) δ 9.03 (d, J=1.5 Hz, 1H), 8.25 (d, J=2.0 Hz, 1H), 5.25 (s, 1H), 3.86 (s, 3M), 1.52 (s, 9H).

1. additionwas added slowly via syringe
2. customquenched with a saturated solution of ammonium chloride
3. customThe organic layer was separated
4. extractionthe aqueous layer was extracted with three portions of ethyl acetate
5. washThe combined organic layers were washed with water
6. dry with materialdried over sodium sulfate
7. concentrationconcentrated in vacuo