1,2-Dibromoethane → HCID 69998640, compound

Participants

Reaction Steps

i)—A solution of 3-methylbutylmagnesium iodide (12 ml), prepared from 1-iodo-3-methylbutane (2.36 ml) and magnesium (0.48 g), activated with 1,2-dibromoethane (0.040 ml), in diethyl ether (10 ml and 10 ml, respectively) at reflux temperature, was added dropwise to (3β,5α,20S)-3-(benzoyloxy)-4,4-dimethylpregna-8,14-diene-20-carboxaldehyde (WO-09852965; 1.55 g) in THF (20 ml). The reaction mixture was stirred at room temperature for 45 min. and then poured into a saturated aqueous solution of ammonium chloride. The product was extracted into ethyl acetate; the combined organic phases were washed with a saturated aqueous solution of ammonium chloride and with brine, dried over magnesium sulfate and concentrated under reduced pressure. Column chromatography afforded (3β,5α,20S,22S)-4,4-dimethylcholesta-8,14-diene-3,22-diol 3-benzoate (1.1 g).

Provenance & Evidence