Benzenesulfonic acid, 4-methyl-, compd. with pyridine (1:1) → 4-Hydroxy-2-methoxymethoxy-6-methyl-benzaldehyde
Reaction equation
[CH3:1][O:2][CH2:3][O:4][C:5]1[CH:12]=[C:11]([O:13]C2CCCCO2)[CH:10]=[C:9]([CH3:20])[C:6]=1[CH:7]=[O:8].CC1C=CC(S([O-])(=O)=O)=CC=1.C1C=C[NH+]=CC=1>CO>[OH:13][C:11]1[CH:10]=[C:9]([CH3:20])[C:6]([CH:7]=[O:8])=[C:5]([O:4][CH2:3][O:2][CH3:1])[CH:12]=1Participants
4
Procedure
To a solution of 2-methoxymethoxy-6-methyl-4-(tetrahydro-pyran-2-yloxy)-benzaldehyde (9.8 g, 34.9 mmol) in MeOH (100 mL) was added PPTS (2.19 g, 8.7 mmol). The reaction mixture was stirred at room temperature for 12 hours then concentrated in vacuo. The residue was purified by silica gel flash column chromatography (hexane:EtOAc 80:20) to give 4-hydroxy-2-methoxymethoxy-6-methyl-benzaldehyde (5.4 g, 79%). 1H NMR (400 MHz, CDCl3): δ 10.47 (s, 1H), 6.65 (s, 1H), 6.57 (d, J=2.0 Hz, 1H), 6.37 (s, 1H), 5.24 (s, 2H), 3.50 (s, 3H), 2.56 (s, 3H). MS (ESI) m/z=195 [M−H]−.