Trifluoroacetic anhydride → 6-methoxy-7-methyl-3,4-dihydronaphthalen-1(2H)-one

Participants

Reaction Conditions

Reaction Steps

A solution of 5.6 g (26.9 mmol) of 4-(3-methoxy-4-methylphenyl)butanoic acid in 100 mL of CH2Cl2 was cooled in ice and treated dropwise with 25 mL of trifluoroacetic anhydride. After stirring at 0° C. for 1 hour, the solution was diluted with Et2O and washed twice with 5% NaOH, then with saturated NaCl. Drying over MgSO4 and removal of the solvent under reduced pressure left the crude product. Chromatography on silica gel, eluting with CH2Cl2 gave 2.79 g (54.7% yield) of the product as a white solid, mp 104-107° C. The structure was confirmed by NMR and mass spectroscopy. MS m/z 191 (M+H+).

Provenance & Evidence