反应 #1857550

反应方程式

(S)-methyl 2-((S)-1-hydroxyethyl)-5-methylhexanoate

((1S,4R)-7,7-dimethyl-2-oxobicyclo[2.2.1]heptan-1-yl)methanesulfonic acid

4-methoxybenzyl 2,2,2-trichloroacetimidate

→

title compound

收率 77.0%

(S)-methyl 2-((S)-1-((4-methoxybenzyl)oxy)ethyl)-5-methylhexanoate

收率 77.0%

溶剂

DCM

反应条件

后处理

1. 1
   其他The reaction mixture was removed from the cold bath
2. 2
   workup.ADDITIONHexane (50 mL) was added to the reaction
3. 3
   其他the precipitate was removed by filtration
4. 4
   洗涤The solids were washed with hexanes (2×10 mL), Celite® (2 scoopula tip-fulls)
5. 5
   workup.ADDITIONwas added to the combined filtrate and washes
6. 6
   其他the solvent was removed under reduced pressure
7. 7
   其他purified

实验过程

To a solution of (S)-methyl 2-((S)-1-hydroxyethyl)-5-methylhexanoate (5.00 g, 26.6 mmol) and ((1S,4R)-7,7-dimethyl-2-oxobicyclo[2.2.1]heptan-1-yl)methanesulfonic acid (camphorsulfonic acid, CSA; 0.617 g, 2.66 mmol) in DCM (53.1 mL) was added 4-methoxybenzyl 2,2,2-trichloroacetimidate (8.27 mL, 39.8 mmol) at 0° C. The reaction mixture was removed from the cold bath and stirred at room temperature for 17 h. Hexane (50 mL) was added to the reaction and the precipitate was removed by filtration. The solids were washed with hexanes (2×10 mL), Celite® (2 scoopula tip-fulls) was added to the combined filtrate and washes, and the solvent was removed under reduced pressure. The resulting adsorbed material was directly loaded onto a column and purified using flash column chromatography (80 g SiO2, 0→35% EtOAc/hexanes) to afford the title compound (6.3 g, 20.4 mmol, 77%) as a colorless oil; 1H NMR (400 MHz, CDCl3) δ 7.24-7.16 (m, 2H), 6.89-6.79 (m, 2H), 4.49 (d, J=11.2 Hz, 1H), 4.33 (d, J=11.1 Hz, 1H), 3.75 (s, 3H), 3.74-3.62 (m, 4H), 2.49 (ddd, J=10.7, 8.2, 4.0 Hz, 1H), 1.62-1.40 (m, 3H), 1.23-1.16 (m, 3H), 1.16-1.03 (m, 2H), 0.87 (d, J=3.9 Hz, 3H), 0.85 (d, J=3.9 Hz, 3H); 13C NMR (101 MHz, CDCl3) δ 175.03, 159.10, 130.63, 129.14, 113.62, 76.16, 70.71, 55.11, 52.64, 51.25, 36.58, 27.97, 26.00, 22.69, 22.17, 17.08; ESIMS m/z 331 ([M+Na]+).

来源