2-Bromoethanol → 4-(2-Hydroxyethoxy)-2-methoxybenzaldehyde

関与物質

反応条件

反応手順

A solution of 4-hydroxy-2-methoxybenzaldehyde (1.217 g, 8.00 mmol) in dry DMF (8.88 mL) was added to a stirred suspension of sodium hydride (60% dispersion in mineral oil) (0.267 mL, 8.00 mmol) in dry DMF (2.22 mL) via cannula at 0° C. under N2. The reaction mixture was stirred at 0° C. for 30 min and warmed to room temperature. 2-bromoethanol (0.851 mL, 12.00 mmol) was added dropwise and the reaction mixture was stirred at 50° C. overnight. The reaction was diluted with water (50 mL) and extracted with EtOAc (3×50 mL). The combined extracts were washed with 1N aq. NaOH (50 mL), dried (MgSO4) and concentrated in vacuo to afford the crude product. This was purified by flash chromatography (Biotage Horizon, 40M, Si, ˜30 mL/min, 100% hexanes for 360 mL, gradient to 60% EtOAc in hexanes over 4536 mL) to afford 4-(2-hydroxyethoxy)-2-methoxybenzaidehyde, as a colorless solid. Rf=0.29 (50% EtOAc/hexanes). LCMS calc.=197.1; found=197.0 (M+H)+. 1H NMR (500 MHz, CHCl3): δ 10.16 (s, 1 H); 7.68 (d, J=8.7 Hz, 1 H); 6.46 (dd, J=8.7, 2.2 Hz, 1 H); 6.40 (d, J=2.2 Hz, 1 H); 4.09 (t, J=4,6 Hz, 2 H); 3.94 (t, J=4.4 Hz, 2 H); 3.79 (s, 3 H); 3.20 (s, 1 H).

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