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

Participants

Reaction Steps

A light yellow suspension of 2,4-dihydroxy-6-methyl-benzaldehyde (4.90 g, 24.98 mmol) in DCM (400 mL) was treated with 3,4-dihydro-2H-pyran (3.5 mL, 38.61 mmol) followed by pyridinium-p-toluenesulfonate (0.20 g, 0.80 mmol). The suspension slowly cleared to a yellow solution. The solution was stirred at rt overnight then diluted with water and washed with saturated NaHCO3. The organic layer was dried (Na2SO4), filtered and concentrated to a yellow oil. The residue was purified by column chromatography (SiO2, EtOAc/hexanes; 1:9) to afford 2-hydroxy-6-methyl-4-(tetrahydro-pyran-2-yloxy)-benzaldehyde (4.60 g, 70%), as a light yellow liquid. 1H NMR (400 MHz, CDCl3) δ 12.33 (s, 1H), 10.09 (s, 1H), 6.45 (d, J=2 Hz, 1H), 6.08 (d, J=2 Hz, 1H), 5.49-5.40 (m, 1H), 3.90-3.80 (m, 1H), 3.65-3.60 (m, 1H), 2.52 (s, 3H), 2.10-1.40 (m, 6H).

Provenance & Evidence