Réaction #472350

Équation de réaction

water

Ethyl aluminum dichloride

methyl acrylate

compound 1.6a

(Z)-3α-Acetoxy-5β-pregna-9(11), 17(20)-diene

→

compound 1.7b

Rendement 70.0%

Methyl 3α-acetoxy-5β-chol-9(11), 16-dien-24-oate

Rendement 70.0%

Solvants

DCM

Conditions de réaction

Traitement

1. 1
   workup.STIRRINGAfter stirring for an additional 20 min at 0° C.
2. 2
   workup.WAITheld there for a further 18 h
3. 3
   AutreThe phases were separated
4. 4
   Extractionthe aqueous layer was extracted with DCM (60 mL)
5. 5
   Lavagewashed sequentially with water (50 mL) and saturated brine solution (100 mL)
6. 6
   SéchageIt was then dried over anhydrous Na2SO4 (5 g)
7. 7
   Filtrationfiltered
8. 8
   ConcentrationThe filtrate was concentrated under vacuum

Mode opératoire

Ethyl aluminum dichloride (14.2 mL, 25 mmol, 1.8M in toluene) was added to a solution of methyl acrylate (1.89 mL, 20 mmol) in DCM (60 mL) at 0° C. under inert atmosphere. The resulting solution was stirred for 15 min and then compound 1.6a (3 g, 8.7 mmol) was added. After stirring for an additional 20 min at 0° C., the temperature was raised to 25° C. and held there for a further 18 h. At this point the reaction was determined to be complete by TLC, then the mixture was poured into cold (0° C.) water (60 mL). The phases were separated and the aqueous layer was extracted with DCM (60 mL). The organic layers were combined and washed sequentially with water (50 mL) and saturated brine solution (100 mL). It was then dried over anhydrous Na2SO4 (5 g) and filtered. The filtrate was concentrated under vacuum, providing compound 1.7b (2.6 g, 70%).

Source