Pyridine, hydrofluoride (1:1) → HCID 69208006, compound

Participants

Reaction Conditions

Reaction Steps

Alternate synthesis of 2-methoxy-3-(vinyl)estra-1,3,5(10)-triene-17β-ol (Compound #25a): Into a solution of 3-triflate-2-methoxyestra-1,3,5(10)-trien-17β-ol (218 mg, 0.5 mmol, prepared as in Shi J. Am. Chem. Soc. 2002, 124, 6921) in 4 mL DMF (anhydrous), was added tributyl(vinyl)Tin(1) (200 μL, 0.6 mmol), lithium chloride (85 mg, 2 mmol), dichlorobis(triphenylphosphine)palladium (II) (10 mg, 0.05 mmol), 2,6-di-tert-butyl-4-methylphenol (2 mg) at room temperature. The reaction was heated at 90° C. for 24 h and then cooled to room temperature. After adding HF-pyridine (4 mL) the reaction mixture was stirred for 16 h. After diluting with EtOAc (20 mL) the reaction mixture was filtered through Celite filter agent and the combined organics were washed with 1 N HCl (1×100 mL), water (1×100 mL), and brine (1×100 mL), then dried with sodium sulfate, filtered, and concentrated via rotary evaporation to give a semi solid viscous oil. The product was purified on a flash silica gel column eluted with a hexane/EtOAc 2:1 mixture to give a white solid product (140 mg, 60%). 1H NMR (CDCl3 δ 7.20 (s, 1 H), 7.00 (dd, J=14, 11 Hz, vinyl, 1H) 6.80 (s, 1 H), 5.70 (d, J=18 Hz, vinyl, 1H), 5.22 (d, J=11 Hz, vinyl, 1H), 3.85 (s, 3H), 2.72 (t, J=4 Hz, 1H), 2.85 (dd, J=5 Hz, 2H), 2.44-1.88 (m, 6 H), 1.80-1.15 (m, 8H), 0.80 (s, 3 H).

Provenance & Evidence