Ethyl Acetate → HCID 59004664, compound

Participants

Reaction Steps

Compound 19 (0.5 g, 1.167 mmol) and tris(dibenzylideneacetone) dipalladium (0) (53.4 mg, 0.058 mmol) were charged to an argon-purged flask fitted with a magnetic stirbar and condenser. Anhydrous tetrahydrofuran (15 mL) was added and stirring begun. Tri-tert-butylphosphine (0.358 mL, 0.1167 mmol, 10 wt % in hexanes) and lithium bis(trimethylsilyl)amide solution (3.501 mL, 3.501 mmol, 1.0 M in THF) were added and the mixture heated to reflux for 2 hours. The solution was cooled to room temperature overnight, diluted with water (15 mL) and 3M sodium hydroxide solution added to adjust pH to 9. Ethyl acetate added and the mixture was transferred to a separatory funnel and the organic layer collected. The aqueous layer was further extracted with ethyl acetate and the combined organic layers were washed with H2O, brine, dried over magnesium sulphate, filtered, concentrated and the crude residue purified twice via chromatography on silica gel (2M NH3 in methanol:CH2Cl2, 5:95) to afford dark red solid 20 (102 mg, 24.0%); 1H NMR (DMSO-d6) δ 8.33 (d, 2H, J=8.7 Hz), 7.82 (d, 2H, J=8.8 Hz), 7.25 (d, 1H, J=8.8 Hz), 6.72 (d, 1H, J=1.8 Hz), 6.63 (m, 1H), 6.49 (s, 1H), 4.64 (brs, 2H), 4.25-4.12 (m, 2H), 2.88-2.78 (m, 1H), 1.99 (s, 3H), 1.91 (q, 1H, J=8.8 Hz), 1.84-1.72 (m, 2H), 1.64-1.55 (m, 1H), 1.52-1.35 (m, 3H), 1.30-1.16 (m, 1H); ESI-MS (m/z, %): 365 (M+1, 100%).

Provenance & Evidence