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

Participants

Reaction Steps

To 100 ml of ethanol, were charged 1.83 ml of ethanol containing 22.2 g of hydrochloric acid dissolved therein, 3.96 g of N-methylaminoacetaldehyde dimethylacetal, 1.0 g of 2-methoxy-3,4-methylenedioxybenzaldehyde, 10 ml of ethanol and 0.12 g of 5% palladium on carbon catalyst, and hydrogenation was carried out at room temperature for 3.5 hours. The amount of hydrogen absorption was 120% 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 1.47 g of 2-methoxy-3,4-methylenedioxy-N-methylbenzylamino dimethylacetal (yield 93%), 0.012 g of 2-methoxy-3,4-methylenedioxybenzylalcohol (yield 1%) and 7.4 mg of 2-methoxy-3,4-methylenedioxy toluene (yield 0.8%), while 2-methoxy-3,4-methylenedioxybenzaldehyde of the starting material not being recognized. The selectivity to the desired 2-methoxy-3,4-methylenedioxy-N-methylbenzylamino dimethylacetal was 99%.

Provenance & Evidence