Diethyl Ether → 3alpha-Nicotinoyloxy-5alpha-pregnan-20-one

Participants

Reaction Conditions

Reaction Steps

To 3α-hydroxy-5α-pregnan-20-one (464 mg, 318.5 g/m, 1.5 mmol) and 4-dimethylaminopyridine (DMAP, 195 mg, 122.17 g/m, 1.6 mmol) dissolved in 10 mL of dry pyridine was added nicotinoyl chloride hydrochloride (285 mg, 178.02 g/m, 1.6 mmol). The reaction mixture was heated at 90° C. for 5 hours and poured into 300 mL of ether. The organic layer was washed twice with saturated sodium bicarbonate, twice with water, dried over magnesium sulfate, and concentrated in vacuo to give the crude product. The crude material was filtered through a bed of silica gel using hexane/ethyl acetate (50:50) elution. The first two fractions gave the titled compound (604 mg, 421 6/m, 1.43 mmol, 96%).

Provenance & Evidence