N-Iodosuccinimide → 5-(2-hydroxyethyl)-6-iodo-2-benzofuran-1(3H)-one

Participants

Reaction Conditions

Reaction Steps

To a cooled (0° C.) solution of 5-(2-hydroxyethyl)-2-benzofuran-1(3H)-one (9.00 g, 50.6 mmol) in 100 mL of TfOH was added NIS (12.5 g, 55.6 mmol), then the mixture was stirred at 0° C. for 2 hrs and then poured into ice-water (500 mL). The solution was extracted three times with 500 mL of EtOAc and the combined organic layers were washed with saturated NaHCO3 and brine, dried over anhydrous sodium sulfate, filtered and concentrated. The residue was purified by column chromatography (EtOAc Petrol Ether=1:5) to give the desired 5-(2-hydroxyethyl)-6-iodo-2-benzofuran-1(3H)-one and regioisomer by-product 5-(2-hydroxyethyl)-4-iodo-2-benzofuran-1(3H)-one. 1H-NMR (400 MHz, CDCl3) δ ppm 7.84 (d, J=7.8 Hz, 1H), 7.46 (d, J=7.8 Hz, 1H), 5.09 (s, 2H), 3.93 (q, J=6.3 Hz, 2H), 3.16 (t, J=6.3 Hz, 2H), 1.45 (t, J=5.5 Hz, 1H).

Provenance & Evidence