反应详情

温度

40 °C

A mixture of nicotinic acid (10 g, 81 mmol), p-toluenesulfonyl chloride (17 g, 89 mmol), benzyltriethylammonium chloride (1.85 g, 8.1 mmol), and potassium carbonate (K2CO3, 44.9 g, 320 mmol) in chloroform (CHCl3, 500 mL) was stirred mechanically at 40° C. for 1 h. Glycine methyl ester hydrochloride (10.2 g, 81 mmol) and K2CO3 (11.2 g, 80 mmol) were then added and stirred at 50° C. for 90 minutes (min). The reaction mixture was filtered through Celite® and the filtrate was concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (2% methanol/ethyl acetate) to give the desired product as an orange gum which solidified upon standing at room temperature (4.7 g, 30%): 1H NMR (400 MHz, CDCl3) δ 9.04 (d, J=2.2 Hz, 1H), 8.76 (dd, J=4.8, 1.5 Hz, 1H), 8.15 (dt, J=8.1, 1.8 Hz, 1H), 7.42 (dd, J=8.1, 4.8 Hz, 1H), 6.84 (br s, 1H), 4.28 (d, J=5.2 Hz, 2H), 3.87 (s, 3H); ESIMS m/z 195 (M+1).

1. stirringstirred at 50° C. for 90 minutes (min)
2. filtrationThe reaction mixture was filtered through Celite®
3. concentrationthe filtrate was concentrated under reduced pressure
4. customThe crude product was purified by silica gel column chromatography (2% methanol/ethyl acetate)