反应详情

温度

0 °C

The 4-hydroxy-3-methylbenzoic acid (10.1 g, 66.38 mmole) was suspended in methanesulfonic acid (50 mL) and cooled to 0° C. (ice bath). Hexamethylenetetramine (18.6 g, 132.75 mmole) was added portionwise over 1 hour. The reaction was warmed to room temperature followed by heating to 90° C. (oil bath) for 5 hours. The reaction was allowed to cool to room temperature and stired for 18 hours. The contents were poured into water (100 mL) and extracted with EtOAc (2×100 mL). The combined extracts were washed with brine (50 mL), dried over MgSO4, filtered and concentrated in vacuo to give an off-white solid (9.0 g, 75%). 1H NMR (DMSO/400 MHz) 12.84 (brs, 1H), 11.40 (s, 1H), 10.09 (s, 1H), 8.20 (s, 1H), 7.98 (s, 1H), 2.21 (s, 3H).

1. temperatureThe reaction was warmed to room temperature
2. temperatureby heating to 90° C. (oil bath) for 5 hours
3. temperatureto cool to room temperature
4. extractionextracted with EtOAc (2×100 mL)
5. washThe combined extracts were washed with brine (50 mL)
6. dry with materialdried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo