反应详情

温度

130 °C

A mixture of methyl 2-hydroxy-5,5-dimethylcyclohex-1-enecarboxylate (26 g, 0.141 mol), methyl 3-amino-4-bromobenzoate (25 g, 0.109 mol), polyphosphoric acid (220 g) and dioxane (220 mL) was heated at 130° C. for 5 hours. After cooling, the mixture was diluted with water. The resulting precipitate was collected by filtration and dried. The solid was suspended in methanol (400 mL), and TMSCl (90 mL) was added. The mixture was stirred at reflux for 5 hours, concentrated and treated with water (80 mL), extracted with ethyl acetate (250 mL). The organic layer was separated, concentrated and recrystallized with methanol to afford desired compound (10.6 g, 27%). 1H NMR (DMSO-d6) δ 10.32 (s, 1H), 7.98 (d, 1H, J=7.2 Hz), 7.10 (d, 1H, J=7.2 Hz), 3.80 (s, 3H), 2.90 (t, 2H, J=6.6 Hz), 2.22 (s, 2H), 1.56 (t, 2H, J=6.6 Hz), and 0.97 (s, 6H). MS (ESI) m/e [M+1]+364.

1. temperatureAfter cooling
2. filtrationThe resulting precipitate was collected by filtration
3. customdried
4. additionTMSCl (90 mL) was added
5. temperatureat reflux for 5 hours
6. concentrationconcentrated
7. additiontreated with water (80 mL)
8. extractionextracted with ethyl acetate (250 mL)
9. customThe organic layer was separated
10. concentrationconcentrated
11. customrecrystallized with methanol