3,4-dihydro-2H-pyran → HCID 10823699, compound

Participants

Reaction Steps

To a mixture of 2,4-dihydroxy-6-methyl-benzaldehyde (6.37 g, 37.88 mmol) in dichloromethane (150 mL) was added 3,4-dihydro-2H-pyran (4.78 g, 56.82 mmol) and pyridium p-toluenesulfonic acid (1.90 g, 7.58 mmol) at room temperature. The resulting mixture was stirred at room temperature for 18 hours then quenched by adding saturated NaHCO3 at 0° C. The organic layer was washed with brine, dried over Na2SO4 and concentrated in vacuo. The residue was purified by silica gel flash column chromatography (EtOAc/hexane=1:3) to give pure product (8.78 g, 98.1%). 1H NMR (400 MHz, CDCl3) δ ppm 12.33 (s, 1H), 10.11 (s, 1H), 6.47 (s, 1H), 6.39 (s, 1H), 5.49 (t, J=3.13 Hz, 1H), 3.78-3.90 (m, 1H), 3.52-3.72 (m, 1H), 2.54 (s, 3H), 1.77-2.03 (m, 3H), 1.53-1.70 (m, 3H); MS (ESI) m/z=285 [M+H]+.

Provenance & Evidence