Methyl iodide → 7-Methoxy-1,1-dimethyl-3,4-dihydronaphthalen-2(1H)-one

Participants

Reaction Steps

7-Methoxy-3,4-dihydro-1H-naphthalen-2-one (Compound A1, 209 g, 1.18 mol), tetrabutylammonium hydrogen sulfate (40 g, 0.118 mol) and methyl iodide (162 g, 2.60 mol) were suspended in THF (500 ml) at room temperature. Under stirring, the mixture was added with 50% aqueous solution of potassium hydroxide (400 g) over 5 minutes. Reflux occurred as the inner temperature rapidly increases. Once the inner temperature stopped to increase, stirring was continued for 45 minutes. The reaction solution was diluted with distilled water (1 L) and extracted twice with CPME (1.5 L). The combined organic layer was washed (distilled water 1 L×3), dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The resulting crude product was recrystallized with MeOH (1 L) and distilled water (500 ml) to obtain the title compound as a colorless needle-like crystal (177 g, 73%).

Provenance & Evidence