Ethyl 4-iodobenzoate → Ethyl 4-[(2,2-dimethyl-4-oxo-chroman-6-yl)ethynyl]-benzoate

Participants

Reaction Steps

A solution of 6-ethynyl-2,2-dimethylchroman-4-one (Compound 262, 2.60 g, 13.0 mmol) and ethyl 4-iodobenzoate (3.6 g, 13.0 mmol) in 50.0 mL Et3N was purged with argon for 15 minutes. To this solution was added bis(triphenylphosphine)-palladium(II) chloride (1.82 g, 2.6 mmol) and copper(I) iodide (496 mg, 2.6 mmol). After sparging for an additional 10 minutes with argon, the solution was stirred overnight at room temperature. The reaction mixture was filtered through a pad of Celite using an Et2O wash. Concentration of the filtrate under reduced pressure, followed by column chromatography (2-5% EtOAc-hexanes) of the residual solid afforded 2.28 g (50%) the title compound as an orange solid. 1H NMR (300 MHz, CDCl3) δ: 8.06 (1H, d, J=2.2 Hz), 8.02 (2H, d, J=8.5 Hz), 2.61 (1H, dd, J=2.2, 8.6 Hz), 7.55 (2H, d, J=8.5 Hz), 6.93 (1H, d, J=8.6 Hz), 4.39 (2H, q, J=7.1 Hz), 2.75 (3H, s), 1.48 (6H, s), 1.41 (t, J=7.1 Hz).

Provenance & Evidence