Pyridine → Trifluoro-methanesulfonic acid 2-(3-benzyloxy-propoxy)-4-chloro-6-formyl-phenyl ester

Participants

Reaction Steps

To a solution of 3-(3-benzyloxy-propoxy)-5-chloro-2-hydroxy-benzaldehyde (5.3 g, 16.6 mmol) and pyridine (3.4 mL, 41.5 mmol) in CH2Cl2 (70 mL) at 0° C. was added Tf2O (3.1 mL, 18.3 mmol) drop-wise over 5 minutes period and the reaction mixture was stirred for 3 h at room temperature. The solution was diluted with CH2Cl2 (100 mL), washed with water, brine, dried over Na2SO4, then concentrated under reduced pressure. The product was purified by silica gel column chromatography (2:1 hexanes-EtOAc mobile phase) generating the title compound (3.8 g, 8.5 mmol, 51%) as a light yellow oil. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 10.18 (s, 1H), 7.48 (d, J=2.3 Hz, 1H), 7.37-7.29 (m, 6H), 4.52 (s, 2H), 4.23 (t, J=6.2 Hz, 2H), 3.69 (t, J=5.8 Hz, 2H), 2.16 (t, J=6.0 Hz, 2H); 19F NMR (376 MHz, CHLOROFORM-d) δ ppm −73.23 (s).

Provenance & Evidence