Triethylamine → Dihydrotestosterone

Participants

Reaction Steps

Triethylamine (TEA) (3.0 mL, 21.5 mmol, 15.5 equiv.) was added to 1.39 mmol of crude 3β-[N-(2-aminoethyl)-amino]-17β-hydroxy-5α-androstane in 8.0 mL dry methanol, followed by 3.21 mL (27.0 mmol, 19.4 equiv.) of ethyl trifluoroacetate (Aldrich). After stirring for 22 h at room temperature, the reaction was concentrated on a rotary evaporator. The residue was partitioned between methylene chloride and aqueous 1N hydrogen chloride (HCl), shaken, and separated. The organic layer was washed with water, saturated aqueous sodium bicarbonate, water, dried over sodium sulfate, filtered, and concentrated under reduced pressure. The product was purified by flash chromatography on a 20 mm column using one column volume of methylene chloride, one column volume of 5% methanol in methylene chloride, and then one column volume of 10% methanol in methylene chloride, as eluants. Isolation and concentration of the product afforded 155 mg (21.2% yield over two steps from 17β-hydroxy-5α-androstan-3-one) of pure product.

Provenance & Evidence