反应详情

Phosphorus oxychloride (8.0 mL, 86 mmol) was added dropwise with stirring to DMF (26 mL, 0.336 mol) the temperature being kept at 10-20° C. This reagent was slowly added to a solution of 2-methylresorcinol (4.84 g, 39 mmol) in 26 mL DMF at 20-30° C. After 30 min the reaction mixture was poured in 2 M aq. NaOH (200 ml), extracted with Et2O (2×100 mL), aqueous phase was neutralized with 5N aq. HCl, the product was extracted with Et2O (2×200 mL), dried and evaporated. The residue was separated on SiO2 (100 g) column, hexane-EtOAc (0 to 20% v/v). Yield 4.1 g (27 mmol, 69%) as white solid. 1H NMR (300 MHz, DMSO): δ 11.61 (s, 1H), 10.79 (s, 1H), 9.71 (s, 1H), 7.43 (d, J=8.4 Hz, 1H), 6.55 (d, J=8.5 Hz, 1H), 1.97 (s, 3H).

1. custombeing kept at 10-20° C
2. extractionextracted with Et2O (2×100 mL), aqueous phase
3. extractionthe product was extracted with Et2O (2×200 mL)
4. customdried
5. customevaporated
6. customThe residue was separated on SiO2 (100 g) column, hexane-EtOAc (0 to 20% v/v)