Nitrogen → HCID 54026644, compound

Participants

Reaction Steps

A mixture of methyl 7-hydroxy-7-methyl-3β-triisopropylsilyloxychol-5-en-24-oate (6) (4.67 g, 8.22 mmoles) and tetrabutylammonium fluoride (1.0M in THF, 49 ml) was heated at 65° in a N2 atmosphere for 30 min. Most of the THF was removed in vacuo. The residue was dissolved in EtOAc (90 ml) and washed with H2O (two times) and saturated brine. The aqueous phases were back-extracted with EtOAc. The combined EtOAc extracts were dried (MgSO4). Evaporation in vacuo and flash chromatography on silica gel with 7% methanol-CH2Cl2 gave 2.08 g of 8 as a yellow-brown foam. NMR (CDCl3) indicated a mixture of 7-isomers: d 0.70 (two peaks, 18-Me); 3.66 (CO2Me); Further elution gave 0.50 g of the tertiary alcohol 7 as a mixture of 7-isomers. NMR (CDCl3): δ 0.70 (two peaks, 18-Me); 1.20 (CMe2OH).

Provenance & Evidence