Dimethylamine, hydrochloride → Ethyl 4-[4-(difluoromethyl)phenoxy]-2-[(dimethylamino)-carbonyl]-1-benzofuran-6-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-[4-(difluoromethyl)phenoxy]-6-(ethoxycarbonyl)-1-benzofuran-2-carboxylic acid (300 mg, 0.80 mmol) in DMF (10 mL) was added HATU (606 mg, 1.59 mmol), DIEA (515 mg, 4.0 mmol) and the solution was stirred at 0° C. for 15 min. Dimethylamine hydrochloride (97.5 mg, 1.20 mmol) was added and the solution was warmed gradually to room temperature and stirred for 14 h. Water was added to the reaction and the product was extracted with CHCl3. The combined organic layers were washed with water twice, dried over MgSO4, and concentrated. The product was purified via gradient silica gel chromatography using CHCl3/MeOH (100/0 to 95/5) to give the title compound (240 mg, 70%) as a light yellow solid. 1H NMR (300 MHz, CHLOROFORM-D) δ ppm 1.38 (t, J=7.16 Hz, 3 H) 3.13 (s, 3 H) 3.32 (s, 3 H) 4.38 (q, J=7.16 Hz, 2 H) 6.64 (t, J=56.61 Hz, 1 H) 7.09 (d, J=8.48 Hz, 2 H) 7.16 (s, 1 H) 7.50 (d, J=8.48 Hz, 2 H) 7.55 (s, 1 H) 8.05 (s, 1 H).

Provenance & Evidence