反应详情

温度

-10 °C

To a solution of 2-hydroxy-4-methoxy-benzaldehyde (30 g, 197 mmol) in DCM (anhydrous, 120 mL) was added pyridine (79 mL, 986 mmol) at room temperature. After the mixture was cooled to −10° C., the Tf2O (50 mL, 296 mmol) was slowly added to the reaction between −10° C. to 0° C. The addition took about 2.5 hours. After the addition, the stirring was kept for 30 minutes. The EtOAc (200 mL) was added. The organic layer was washed with 1 M HCl (3×80 mL), dried over MgSO4, filtered, and evaporated under vacuum. The residue was purified over silica gel, eluting with 5% EtOAc/hexanes to give trifluoro-methanesulfonic acid 2-formyl-5-methoxy-phenyl ester (2) 46 g in 82% yield. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 10.13 (s, 1 H), 7.95 (d, J=8.99 Hz, 1 H), 7.03 (dd, J=8.60, 2.34 Hz, 1 H), 6.88 (d, J=2.34 Hz, 1 H), 3.93 (s, 3 H)

1. additionThe addition
2. additionAfter the addition
3. waitthe stirring was kept for 30 minutes
4. washThe organic layer was washed with 1 M HCl (3×80 mL)
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. customevaporated under vacuum
8. customThe residue was purified over silica gel
9. washeluting with 5% EtOAc/hexanes