Hydrochloric Acid → 1,3-Benzodioxole, 5-(chloromethyl)-

Participants

Reaction Conditions

Reaction Steps

In a 500-ml flask were placed 30 g (0.2 mol) of piperonyl alcohol, 102.8 g (1.0 mol) of a 35% aqueous hydrochloric acid solution and 150 ml of toluene. They were stirred in a nitrogen stream at 90° C. for about 2 hours. The stirring was stopped and phase separation was made to remove the aqueous phase. The toluene phase was washed with water and an aqueous NaHCO3 solution in this order, and then with water several times. The toluene phase was concentrated under reduced pressure to obtain 32.28 g of piperonyl chloride. In a 500-ml flask were placed 8.4 g (0.21 mol) of sodium hydride and 100 ml of toluene, and they were stirred under refluxing in a nitrogen stream, in a 120° C. oil bath. Thereto was dropwise added, in 20 minutes, 29.6 g (0.19 mol) of 1-menthol dissolved in 30 ml of toluene. 30 minutes later, 32.3 g (0.19 mol) of the piperonyl chloride dissolved in 32 ml of toluene was added dropwise, followed by stirring for about 1 hour. The stirring was stopped and 110 ml of a 2 N aqueous hydrochloric acid solution was added to terminate a reaction, after which phase separation was made. The toluene phase was washed with water three times and then concentrated. The resulting concentrate was distilled for purification to obtain 35.6 g (yield: 30.6%, purity: 97.2%) of piperonyl 1-mentyl ether as a transparent oily substance.

Provenance & Evidence