反应详情

To ((E)-(2S,3S,4S,5S)-3,5-Dimethoxy-2,4-dimethyl-oct-6-enyloxymethyl)-benzene (5.5 g, 18.0 mmol) in anhydrous THF (180 ml) at −78° C. and under an atmosphere of nitrogen, was slowly added LiDBB until a dark green colour persisted. The temperature was maintained below −70° C. during the addition. The reaction was quenched with saturated ammonium chloride, allowed to warm to room temperature and extracted with diethyl ether (2×). The combined organic layers were dried over magnesium sulphate, filtered and concentrated in vacuo. The product was purified by flash chromatography (SiO2, iHex/EtOAc, 50:1 then 1:1) to afford 3.6 g (93%) as a clear oil. 1H NMR (300 MHz, CDCl3) δ 5.66 (dq, J=15.2 Hz, 6.4 Hz, 1H), 5.19 (dd, J=15.2 Hz, 8.8 Hz, 1H), 3.75-3.52 (m, 3H), 3.49 (s, 3H), 3.31 (t, J=9.1 Hz, 1H), 3.24 (s, 3H), 2.82 (dd, J=8.2 Hz, 2.9 Hz, 1H), 1.91 (m, 1H), 1.77 (d, J=6.4 Hz, 3H), 1.68 (m, 1H), 0.84 (d, J=6.9 Hz, 3H), 0.79 (d, J=7.1 Hz, 3H).

1. customat −78° C.
2. temperatureThe temperature was maintained below −70° C. during the addition
3. customThe reaction was quenched with saturated ammonium chloride
4. extractionextracted with diethyl ether (2×)
5. dry with materialThe combined organic layers were dried over magnesium sulphate
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customThe product was purified by flash chromatography (SiO2
9. customiHex/EtOAc, 50:1 then 1:1) to afford 3.6 g (93%) as a clear oil