تفاعل #1857550

معادلة التفاعل

(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

المردود 77.0%

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

المردود 77.0%

المذيبات

DCM

ظروف التفاعل

المعالجة

1. 1
   أخرىThe reaction mixture was removed from the cold bath
2. 2
   workup.ADDITIONHexane (50 mL) was added to the reaction
3. 3
   أخرىthe precipitate was removed by filtration
4. 4
   غسيلThe 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
   أخرىthe solvent was removed under reduced pressure
7. 7
   أخرىpurified

الإجراء التجريبي

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]+).

المصدر