Water → (E)-Methyl 3alpha-acetoxy-5beta-chol-9(11),16,22-trien-24-oate

Temperature

25 °C

Ethyl aluminum dichloride (104.5 mL, 192 mmol, 1.8 M in toluene) was added to a solution of methyl propiolate (13.58 mL, 153 mmol) in DCM (100 mL) at 0° C. under inert atmosphere. The resulting solution was stirred for 15 min and then compound 1.6a (22 g, 64.3 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, and the mixture was poured into cold (0° C.) water (200 mL). The phases were separated and the aqueous layer was extracted with DCM (150 mL). The organic layers were combined and washed sequentially with water (200 mL) and saturated brine solution (100 mL). It was then dried over anhydrous Na2SO4 (40 g) and filtered. The filtrate was concentrated under vacuum and the resulting solid was purified by slurring in methanol (280 mL) to provide compound 1.7a (17.5 g 68%) as a white solid.

1. stirringAfter stirring for an additional 20 min at 0° C.
2. waitheld there for a further 18 h
3. customThe phases were separated
4. extractionthe aqueous layer was extracted with DCM (150 mL)
5. washwashed sequentially with water (200 mL) and saturated brine solution (100 mL)
6. dry with materialIt was then dried over anhydrous Na2SO4 (40 g)
7. filtrationfiltered
8. concentrationThe filtrate was concentrated under vacuum
9. customthe resulting solid was purified

ORD record

ord-2cd6436570ef45839e2e2d95b87d9721

Source dataset

uspto-grants-2013_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08367852B2