Potassium Carbonate → Methyl 6-(2-morpholinoethoxy)benzofuran-2-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a stirred solution of 267 (650 mg, 3.39 mmol) in a 1:1 mixture of DMF-acetone (20 mL) was added 4-(2-chloroethyl)morpholine (630 mg, 3.39 mmol) and potassium carbonate (937 mg, 6.78 mmol). The reaction mixture was stirred at 60° C. for 72 hours. The solvents were removed under reduced pressure and water (50 mL) was added to the residue. 2M Sodium carbonate solution (20 mL) was added and the resultant solution was extracted with ethyl acetate (2×40 mL). The organic phase was separated, dried with sodium sulfate and the solvents removed under reduced pressure. The residue was purified by flash chromatography on silica gel, eluting with a gradient of 1:1 ethyl acetate-hexanes, then ethyl acetate, then 9:1 ethyl acetate-methanol. This afforded 268 as a clear oil (760 mg, 73% yield). 1H NMR: (DMSO) δ 7.67-7.63 (m, 2H), 7.32 (s, 1H), 6.98 (d, J=8.5 Hz, 1H), 4.14-4.16 (m, 2H), 3.85 (s, 3H), 3.57-3.55 (m, 4H), 2.88-2.86 (m, 2H), 2.72-2.70 (m, 4H).

Herkunft & Nachweise