Equilin → 17-Methylenestra-1,3,5(10),7-tetraen-3-ol

Participants

Reaction Steps

Methyltriphenylphosphonium bromide (1.9967 g, 5.5892 mmol) and potassium t-butoxide (627.2 mg, 5.589 mmol) suspended in 6.1 mL of anh. DMSO under argon were 1 h in an oil bath (71-83° C., after which equilin (300.0 mg, 1.118 mmol) in 6.1 mL of anh. DMSO was added via syringe. See FIG. 18. After stirring a further 70 min., the reaction mixture was poured into 40 mL of ice water and extracted three times with 25 mL portions of ether. The combined organic extracts were washed with 25 mL of brine, dried over magnesium sulfate, and filtered through diatomaceous earth. The residue was washed with 10 mL of ether and the combined filtrates were concentrated under reduced pressure. Flash chromatography (15% ethyl acetate/hexanes on silica gel) followed by preparative TLC (20% ethyl acetate/hexanes on silica gel GF, 1000μ thickness) gave an opaque white film (162.3 mg, 0.6093 mmol, 54%).

Provenance & Evidence