Acetic Acid → HCID 86761361, compound

Participants

Reaction Conditions

Reaction Steps

The mixture containing 1α,3β-bis(tert-butyldimethylsilyloxy)-20(S)-(1-ethyl-1-methylpropoxycarbonylmethoxy)pregna-5,7-diene from Example 23(2) (5.59 g), a 1M tetrahydrofuran solution of tetra-n-butylammonium fluoride (79.5 ml, 79.5 ml) and acetic acid (2 ml) were mixed and stirred at an external temperature of 65° C. for 17 hours. After cooling to room temperature, the reaction mixture was diluted with ethyl acetate, washed sequentially with aqueous potassium bisulfate, saturated aqueous sodium bicarbonate and saturated aqueous sodium chloride, and then dried over anhydrous magnesium sulfate. After evaporation under reduced pressure to remove the solvent, the resulting residue was purified by column chromatography (hexane:ethyl acetate:ethanol=5:5:0.3) to give the titled compound (2.43 g, 57% for 2 steps) as a pale yellow foam.

Provenance & Evidence