Reaktion #1857551

Reaktionsgleichung

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

→

(S)-2-((S)-1-((4-methoxybenzyl)oxy)ethyl)-5-methylhexanal

Lösungsmittel

DCM

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeat 0° C
2. 2
   SonstigeThe flask was removed from the cold bath
3. 3
   Temperaturcooled
4. 4
   workup.ADDITIONmixture of diethyl ether (Et2O; 60 mL) and 2 Normal (N) HCl (20 mL) over 15 min
5. 5
   SonstigeThe mixture was removed from the cold bath
6. 6
   workup.STIRRINGstirred at room temperature for 30 min
7. 7
   SonstigeThe phases were separated
8. 8
   Extraktionthe aq. phase was further extracted with Et2O (2×50 mL)
9. 9
   Waschenwashed with sat. aq. sodium bicarbonate (NaHCO3; 25 mL) and brine (25 mL)
10. 10
    Trocknendried over Na2SO4
11. 11
    Filtrationfiltered
12. 12
    workup.ADDITIONthe filtrate treated with Celite® (5 scoopula tip-fulls)
13. 13
    SonstigeThe solvent was removed under reduced pressure
14. 14
    Sonstigepurified

Vorschrift

To a solution of (S)-methyl 2-((S)-1-((4-methoxybenzyl)oxy)ethyl)-5-methylhexanoate (6.00 g, 19.5 mmol) and chlorobis(cyclooctene)-iridium(I) dimer (0.349 g, 0.389 mmol) in dry DCM (19.5 mL) was slowly added Et2SiH (3.76 mL, 29.2 mmol) at 0° C. The flask was removed from the cold bath and the reaction was stirred at room temperature for 20 h under nitrogen (N2). The reaction mixture was transferred via cannula to an ice-cooled mixture of diethyl ether (Et2O; 60 mL) and 2 Normal (N) HCl (20 mL) over 15 min. The mixture was removed from the cold bath and stirred at room temperature for 30 min. The phases were separated and the aq. phase was further extracted with Et2O (2×50 mL). The organics were combined, washed with sat. aq. sodium bicarbonate (NaHCO3; 25 mL) and brine (25 mL), dried over Na2SO4, filtered, and the filtrate treated with Celite® (5 scoopula tip-fulls). The solvent was removed under reduced pressure and the resulting adsorbed material was directly loaded onto a column and purified using flash column chromatography (120 g SiO2, 0→75% EtOAc/hexanes) to afford the intermediate aldehyde, (S)-2-((S)-1-((4-methoxybenzyl)oxy)ethyl)-5-methylhexanal.

Quelle