反应详情

To a stirred slurry LiAlH4 (0.114 g, 3 mmol) in anhydrous Et2O (5 ml) was added drop wise the solution of ethyl-6-methoxybenzofuran-2-carboxylate (0.380 g, 1.73 mmol) and stirring was continued for 0.5 h at room temperature. The reaction mixture was quenched with EtOAc:H2O:MeOH mixture (7:3:1), diluted to 20 ml with EtOAc and filtered through Celite. The filtrate was evaporated and the residue was dried in vacuo to give the creamy paste (0.324 g) which was used as such for next step. This (0.310 g) was dissolved in anhydrous dioxane (10 ml) and MnO2 (1 g, excess) was added to it. The suspension was stirred at reflux for 3 h, cooled to room temperature and filtered through Celite pad. The filtrate was evaporated to dryness and the residue was purified by FCC (SiO2, hexane: EtOAc; 70:30), to give the title compound (0.182 g; 76%), as light pink crystalline solid. 1H-NMR (CDCl3) 3.87 (s, 3H); 6.96 (dd, 1H, J=2.22, 8.73 Hz); 7.03 (d, 1H, J=1.83 Hz); 7.48 (5, 1H); 7.59 (d, 1H, J=8.7 Hz); 9.74 (s, 1H).

1. customThe reaction mixture was quenched with EtOAc
2. additionH2O:MeOH mixture (7:3:1), diluted to 20 ml with EtOAc
3. filtrationfiltered through Celite
4. customThe filtrate was evaporated
5. customthe residue was dried in vacuo
6. customto give the creamy paste (0.324 g) which
7. stirringThe suspension was stirred
8. temperatureat reflux for 3 h
9. filtrationfiltered through Celite pad
10. customThe filtrate was evaporated to dryness
11. customthe residue was purified by FCC (SiO2, hexane: EtOAc; 70:30)