Trifluoroacetic acid → 7-hydroxy-4-methyl-2H-chromene-3-carbaldehyde

Reaktionsgleichung

C([O:8][C:9]1[CH:18]=[C:17]2[C:12]([C:13]([CH3:21])=[C:14]([CH:19]=[O:20])[CH2:15][O:16]2)=[CH:11][CH:10]=1)C1C=CC=CC=1.CC1C=C(C)C(C)=C(C)C=1C.C(O)(C(F)(F)F)=O.C([O-])(O)=O.[Na+]>>[OH:8][C:9]1[CH:18]=[C:17]2[C:12]([C:13]([CH3:21])=[C:14]([CH:19]=[O:20])[CH2:15][O:16]2)=[CH:11][CH:10]=1

Komponenten

Edukt 4

HCID 6422Trifluoroacetic acid

HCID 12784Pentamethylbenzene

HCID 516892Sodium Bicarbonate

HCID 584387777-(benzyloxy)-4-methyl-2H-chromene-3-carbaldehyde

Produkt 1

HCID 584391347-hydroxy-4-methyl-2H-chromene-3-carbaldehydeAusbeute 83,3 %

Versuchsvorschrift

To 7-(benzyloxy)-4-methyl-2H-chromene-3-carbaldehyde (230 mg) and 1,2,3,4,5-pentamethylbenzene (608 mg) was added TFA (3 mL), followed by stirring at room temperature overnight. The reaction liquid was poured into an aqueous NaHCO3 solution, followed by extraction with EtOAc three times. The organic layer was combined, washed with brine, dried over MgSO4, and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (automatic purification device, hexane:EtOAc=80:20 to 20:80) to obtain 7-hydroxy-4-methyl-2H-chromene-3-carbaldehyde (130 mg) as a pale yellow powder.