3,4-dihydro-2H-pyran → HCID 19025355, compound

HRID 1033154Notes

Reaction equation

HRID 1033154 reaction equation
[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([O:9][CH3:10])=[CH:5][C:4]=1[OH:11].COC1C=CC([O:22][CH3:23])=CC=1C=O.[O:24]1C=CCCC1.C([Li])CCC>CN(C=O)C.CCOCC>[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([O:9][CH3:10])=[C:5]([C:23]([OH:22])=[O:24])[C:4]=1[OH:11]

Participants

7

Reactant 4

HCID 80803,4-dihydro-2H-pyranHCID 667262,5-Dimethoxybenzaldehyde2×HCID 53144982,5-DimethoxyphenolHCID 178418339Butyllithium

Product 1

HCID 19025355HCID 19025355, compound

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolventHCID 6228DimethylformamideSolvent

Procedure

Treatment of 2,5-dimethoxybenzaldehyde with m-chloroperbenzoic acid provides, after workup, 2,5-dimethoxyphenol. Protection of the phenol can be accomplished by formation of a THP ether using dihydropyran and acid. Formylation of the resultant compound can be carried out using butyllithium and DMF. Subsequent acidification liberates the phenol to yield 3,6-dimethoxysalicylic acid.

Sources & evidence

ORD record
ord-0293a77c65264027a50f160bc643feb2
Source dataset
uspto-grants-1994_05
Patent number
US05310682

Reaction notes

Loading…