Tetrabutylammonium Fluoride → HCID 70146720, compound

Participants

Reaction Steps

The diene disilane prepared above is redissolved in THF (300 mL) and treated with tetrabutylammonium fluoride (1.0 M in THF; 35.0 mL, 35.0 mmole). The desilylation reaction occurs over 20 minutes with stirring at ambient temperature. The reaction mixture is then diluted with EtOAc (500 mL) and washed with brine (3×400 mL). The crude product solution is dried over MgSO4, filtered and evaporated to dryness. The crude product is purified by flash chromatography (1:1 EtOAc/CH2Cl2) to afford 17β-hydroxy-4-trimethylsilyl-7-ethyloxycarbonylmethylene-4-aza-androst-5-en-3-one as a mixture of the E and Z isomers (diolefin). The diolefin is then hydrogenated in a manner similar to that described in Example 7H to give 7β-ethoxycarbonylmethyl-17β-hydroxy-4-aza-5α-androstan-3-one. The compound has the following structure:

Provenance & Evidence