Hydrochloric Acid → 2-Methoxy-3,4-methylenedioxytoluene

Participants

Reaction Steps

To 100 ml of ethanol, were charged 0.18 ml of ethanol containing 22.2 g of hydrochloric acid dissolved therein, 0.79 g of N-methylaminoacetaldehyde dimethylacetal, 1.0 g of 2-methoxy-3,4-methylenedioxybenzaldehyde, 0.12 g of 5% palladium on carbon catalyst and 10 ml of ethanol, and hydrogenation was carried out in an oil bath at 70° C. for 2 hours. The amount of hydrogen absorption was 100% of the theoretical amount. After the reaction was over, the catalyst was filtered out and 2N NaOH aqueous solution was added to the reaction mixture to make the filtrate alkaline (pH 11). The resulting mixture was then extracted with ethyl acetate. The liquid extract was analyzed by GC and LC to show 1.32 g of 2-methoxy-3,4-methylenedioxy-N-methylbenzylamino dimethylacetal (yield 84%), 0.02 g of 2-methoxy-3,4-methylene-dioxybenzylalcohol (yield 2%), 0.076 g of 2-methoxy-3,4-methylenedioxytoluene (yield 8%) and 0.007 g of 2-methoxy-3,4-methylenedioxybenzaldehyde of the starting material (conversion rate:99%). The selectivity to the desired 2-methoxy-3,4-methylenedioxy-N-methylbenzylamino dimethylacetal was 98%.

Provenance & Evidence