Hydrochloric Acid → HCID 11742322, compound

Participants

Reaction Steps

A mixture of 436 mg (1.0 mmole) of 4-methyl-17-triflluoromethylsulfonyloxy-4-aza-5α-androst-16-en-3-one (60) (Case 18730), 168 mg (1.5 mmoles) of methyl 4-pentynoate, 40 mg of bis(triphenylphosphine)palladium(II) acetate, 5 mg of cuprous iodide in 3.0 ml of DMSO and 3.0 ml of N,N-diisopropylamine was stirred at room temperature for 17 hrs. The dark reaction mixture was poured into 50 ml of 0.5M HCl and extracted with CH2Cl2 (3×). The combined extracts were washed with water (4×) and dried (MgSO4). Evaporation in vacuo and flash chromatography of the residue on silica gel with 6:1 CH2Cl2 -acetone gave 400 mg of enyne 61. The enyne was immediately hydrogenated in 20 ml of EtOH with 150 mg of 10% palladium on carbon catalyst under a hydrogen-filled balloon. After stirring at room temperature for 24 hrs, the reaction mixture was filtered through a bed of Celite., which was washed with EtOH (4×). The filtrate and washes were evaporated in vacuo and the residue flash chromatographed on silica gel with 5:1 CH2Cl2 to give 345 mg of methyl 4-methyl-3-oxo-21-nor-4-aza-5α-cholane-24-carboxylate (62).

Provenance & Evidence