((E)-(2S,3S,4S,5S)-3,5-Dimethoxy-2,4-dimethyl-oct-6-enyloxymethyl)-benzene → (E)-(2S,3S,4S,5S)-3,5-Dimethoxy-2,4-dimethyl-oct-6-en-1-ol
Reaction equation
[CH3:1][O:2][C@H:3]([C@@H:15]([CH3:22])[C@@H:16]([O:20][CH3:21])/[CH:17]=[CH:18]/[CH3:19])[C@@H:4]([CH3:14])[CH2:5][O:6]CC1C=CC=CC=1>C1COCC1>[CH3:1][O:2][C@H:3]([C@@H:15]([CH3:22])[C@@H:16]([O:20][CH3:21])/[CH:17]=[CH:18]/[CH3:19])[C@@H:4]([CH3:14])[CH2:5][OH:6]Participants
Reactant 1
Product 1
Reagents, catalysts & solvents 1
Procedure
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).
Workup
- customat −78° C.
- temperatureThe temperature was maintained below −70° C. during the addition
- customThe reaction was quenched with saturated ammonium chloride
- extractionextracted with diethyl ether (2×)
- dry with materialThe combined organic layers were dried over magnesium sulphate
- filtrationfiltered
- concentrationconcentrated in vacuo
- customThe product was purified by flash chromatography (SiO2
- customiHex/EtOAc, 50:1 then 1:1) to afford 3.6 g (93%) as a clear oil
Sources & evidence
- ORD record
- ord-080796f677684bb28bf9be965ab8352c
- Source dataset
- uspto-grants-2015_01
- Patent number
- US08933015B2
Reaction notes
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