反应详情

To a solution of diisopropylethyl amine (5.59 g, 55.30 mmol) in anhydrous tetrahydrofuran (150 mL) was added a solution of butyllithium (1.6 M in hexanes, 34.5 mL, 55.30 mmol) at 0° C. The reaction solution was stirred at the same temperature for 1 hour, then added a solution of ethyl 1,4-dioxaspiro[4.5]decane-8-carboxylate (10.80 g, 50.00 mmol) in anhydrous tetrahydrofuran (20 mL) at −78° C. The reaction mixture was stirred at the same temperature for 1 h then added phenylselenium bromide (11.90 g, 50.70 mmol). The mixture was continued to stir at −78° C. for 5 hour, then at ambient temperature for 16 hour. The reaction was quenched with saturated sodium hydrogencarbonate (200 mL), diluted with ethyl acetate (200 mL), saturated ammonium chloride (3×150 mL), brine (3×100 mL), dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated in vacuo to dryness. The residue was purified by column chromatography with ethyl acetate in hexanes (10%) to afford the title compound as a viscous liquid (14.10 g, 76%): 1H NMR (300 MHz, CDCl3) δ 7.54 (d, J=7.6 Hz, 1H), 7.37-7.32 (m, 1H), 7.26 (dd, J=7.0, 7.0 Hz, 2H), 4.05 (dd, J=7.1 Hz, 2H), 3.90 (d, J=3.4 Hz, 4H), 2.20-2.12 (m, 2H), 2.00-1.88 (m, 2H), 1.82-1.70 (m, 2H), 1.57-1.46 (m, 2H), 1.14 (t, J=7.1 Hz, 3H).

1. stirringThe reaction mixture was stirred at the same temperature for 1 h
2. stirringto stir at −78° C. for 5 hour
3. waitat ambient temperature for 16 hour
4. customThe reaction was quenched with saturated sodium hydrogencarbonate (200 mL)
5. additiondiluted with ethyl acetate (200 mL), saturated ammonium chloride (3×150 mL), brine (3×100 mL)
6. dry with materialdried over anhydrous sodium sulfate
7. filtrationfiltered
8. concentrationThe filtrate was concentrated in vacuo to dryness
9. customThe residue was purified by column chromatography with ethyl acetate in hexanes (10%)