Lithium tri-tert-butoxyaluminohydride → Methyl 3-acetyloxy-12-hydroxydeoxycholan-24-ate

A THF solution of lithium tri-tert-butoxyaluminum hydride (1 M, 22.4 mL, 22.4 mmol) was added drop wise to a solution of compound 2.0a (2.5 g, 5.6 mmol) in THF (25 mL) at ambient temperature. After stirring for an additional 4-5 h, the reaction was determined to be complete by TLC. The reaction was quenched by adding aqueous HCl (1 M, 10 mL) and the mixture was diluted with EtOAc (30 mL). The phases were separated and the organic phase was washed sequentially with water (15 mL) and saturated brine solution (10 mL). The organic phase was then dried over anhydrous Na2SO4 (3 g) and filtered. The filtrate was concentrated under vacuum and the resulting solid was purified by column chromatography [29 mm (W)×500 mm (L), 60-120 mesh silica, 50 g], eluting with EtOAc/hexane (2:8) [5 mL fractions, monitored by TLC with p-anisaldehyde charring]. The fractions containing the product were combined and concentrated under vacuum to provide compound 2.1a (2.3 g, 91%) as a white solid.

1. customThe reaction was quenched
2. additionby adding aqueous HCl (1 M, 10 mL)
3. additionthe mixture was diluted with EtOAc (30 mL)
4. customThe phases were separated
5. washthe organic phase was washed sequentially with water (15 mL) and saturated brine solution (10 mL)
6. dry with materialThe organic phase was then dried over anhydrous Na2SO4 (3 g)
7. filtrationfiltered
8. concentrationThe filtrate was concentrated under vacuum
9. customthe resulting solid was purified by column chromatography [29 mm (W)×500 mm (L), 60-120 mesh silica, 50 g]
10. washeluting with EtOAc/hexane (2:8) [5 mL fractions, monitored by TLC with p-anisaldehyde charring]
11. additionThe fractions containing the product
12. concentrationconcentrated under vacuum

ORD-Eintrag

ord-d2ea755c69b54920a7f7ab6f88403048

Quelldatensatz

uspto-grants-2013_02

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08367852B2