反应详情

To a cold solution of methyl 4-aminobenzoate (15.0 g, 0.099 mol) in conc. HCl was added aq. solution of sodium nitrite (7.5 g, 0.109 mmol) at 0-5° C. The reaction mass was stirred at RT for 1-2 h. The reaction mass was cooled to 0° C. and stannous chloride (0.049 g, 0.210 mmol) was added and further stirred at RT for 2-3 h. The reaction mass was filtered to afford 17.0 g of desired product. 1H NMR (300 MHz, DMSO d6): δ 3.77 (s, 3H), 7.03 (d, J=8.4 Hz, 2H), 7.82 (d, J=8.4 Hz, 2H), 10.69 (br s, 2H); MS (m/z): 167.28 (M+H)+.

1. temperatureThe reaction mass was cooled to 0° C.
2. stirringfurther stirred at RT for 2-3 h
3. filtrationThe reaction mass was filtered