Diethyl Ether → HCID 22983888, compound

Participants

Reaction Steps

Under argon atmosphere, a solution of 5-androsten-3,17-dione 3-ethyleneketal 10 (4.95 g, 0.0150 mol) in anhydrous THF (150 mL) was cooled at 0° C. and treated with 1.0 M solution of lithium bis(trimethylsilyl)amide in THF (18 mL, 0.018 mol). The solution was stirred 20 min at room temperature, cooled at −78° C., and treated with chlorotrimethylsilane (2.24 mL, 0.0176 mol). The reaction was allowed to warm to room temperature, then evaporated. The residue was diluted with dichloromethane, washed two times with water and brine, dried over magnesium sulfate, filtered, and evaporated. A solution of the crude silylenol ether in a dichloromethane-acetonitrile 2-5 (140 mL) was treated with palladium acetate (4.04 g 0.0180 mol) and refluxed for 30 min. The reaction mixture was cooled to room temperature and evaporated. The black residue was purified by flash chromatography (hexanes-ethyl acetate 4-1) to provide the enone 44 (3.49 g, 71%): 1H NMR (300 MHz, CDCl3) δ 1.085 (s, 3H), 1.09 (s, 3H), 1.21-1.93 (m, 11H), 2.15 (dd, J=2.7 and J=14.1 Hz, 1H), 2.26-2.34 (m, 2H), 2.58 (d, J=14.1 Hz, 1H), 3.95 (m, 4H), 5.40 (d, J=5.1 Hz, 1H), 6.04 (dd, J=3.2 and J=6 Hz, 1H), 7.50 (d, J=5.8 Hz, 1H).

Provenance & Evidence