反应详情

温度

135 °C

A mixture of ethyl 2-(ethoxymethylene)-3-oxobutanoate (100 g, 0.54 mol) and 2-methoxy-5-aminopyridine (67 g, 0.54 mol) in chlorobenzene (500 mL) was heated at 135° C. for 4 h in a round bottomed flask that was equipped with a distillation apparatus to collect the ethanol generated during the reaction. The reaction mixture was cooled and concentrated and the residue was triturated in diethylether and filtered to obtain the desired product (120 g, 84%) as an off-white solid: 1H NMR (500 MHz, CDCl3) δ 12.74 (d, 12.3 Hz, 1H), 8.35 (d, J=13.0 Hz, 1H), 8.07 (d, J=2.8 Hz, 1H), 7.55 (d, J=8.8, 2.9 Hz, 1H), 6.79 (d, J=8.8 Hz, 1H), 4.30 (q, J=7.1 Hz, 2H), 2.55 (s, 3H), 1.33 (t, J=7.1 Hz, 1H); ESI MS m/z 265 [M+H]+.

1. customwas equipped with a distillation apparatus
2. customto collect the ethanol
3. customgenerated during the reaction
4. temperatureThe reaction mixture was cooled
5. concentrationconcentrated
6. customthe residue was triturated in diethylether
7. filtrationfiltered