Hydroxy-[2-(4-methoxy-phenyl)-6-methyl-imidazo[1,2-a]pyridin-3-yl]-acetic acid ethyl ester → [2-(4-Methoxy-phenyl)-6-methyl-imidazo[1,2-a]pyridin-3-yl]-acetic acid ethyl ester

Participants

Reaction Steps

To a magnetically stirred solution of hydroxy-[2-(4-methoxy-phenyl)-6-methyl-imidazo[1,2-a]pyridin-3-yl]-acetic acid ethyl ester 13b (0.72 g, 2.11 mmol) in DCM (21 mL) under Ar atmosphere was added P2I4 (0.84 g mg, 1.48 mmol). The reaction mixture was stirred at room temperature for 4 h. Aqueous NaH2CO3 (100 mL) was added, and the aqueous phase was extracted with dichloromethane (20 mL). The combined organic layers were washed with water (100 mL), dried (MgSO4), and concentrated in vacuo to the crude product. The pure product was obtained by column chromatography over silica gel (40:60 EtOAc/hexane, then 100% EtOAc as eluent), which gave the title compound (0.29 g, 42%) as an off white solid. 1H NMR (400 MHz, CDCl3) δ 1.25 (t, J=7.3 Hz, 3H), 2.33 (s, 3H), 3.82 (s, 3H), 3.96 (s, 2H), 4.19 (q, J=7.3 Hz, 2H), 6.97 (d, J=8.8 Hz, 2H), 7.04 (dd, J=1.4, 9.1 Hz, 1H), 7.53 (d, J=9.1 Hz, 1H), 7.73 (d, J=8.8 Hz, 2H), 7.85 (s, 1H).

Provenance & Evidence