Safrole is a colorless or slightly yellow oily liquid. It is typically extracted from the root-bark or the fruit of sassafras plants in the form of sassafras oil, or synthesized from other related methylenedioxy compounds. It is the principal component of brown camphor oil, and is found in small amounts in a wide variety of plants, where it functions as a natural pesticide. The Octea cymbarum oil made of the Octea pretiosa, a plant growing in Brazil, and sassafras oil made of the Sassafras albidum, a plant growing in eastern North America, are the main natural sources for safrole. It has a characteristic "candy-shop" aroma.
It is a precursor in the synthesis of the insecticide synergist piperonyl butoxide.
Safrole is a weak carcinogen. It naturally occurs in a variety of spices, for example basil, cinnamon, nutmeg, and pepper. In that role safrole is believed to make a small but measurable contribution to the overall incidence of human cancer. In the US, it was once widely used as a food additive in root beer, sassafras tea, and other common goods, but was banned by the Food and Drug Administration (FDA) after its carcinogenicity was discovered. Today, safrole is also banned for use in soap and perfumes by IFRA.
Use in ecstasy manufactureSafrole is often used as the precursor for the clandestine manufacture of MDMA (ecstasy). The standard synthetic procedure for the production of MDMA from safrole is via isomerization in the presence of a strong base to isosafrole, oxidation to 3,4-methylenedioxy phenyl-2-propanone, finally a reductive amination with either methylamine (to make MDMA) or ethylamine (to make MDEA) or ammonia (to make MDA). A newer synthesis method makes use of the Wacker process (palladium(II) chloride catalyst and 1,4-benzoquinone) to oxidize safrole directly to the 3,4-methylenedioxy phenyl-2-propanone intermediate.
It is nearly impossible to obtain large quantities of safrole and/or sassafras oil without arousing the suspicion of law enforcement, as both safrole and isosafrole as well as piperonal are Category I precursors under regulation No 273/2004 of the European Community. In the US, safrole is currently a List I chemical. The root bark of American sassafras contains a few percent of steam volatile oil which is typically 75% safrole. Attempts to access safrole from this source are generally not successful as the yield is low and the effort required to get useful amounts of material is great. Safrole is listed as a Table I precursor under the United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances.
safrole in Danish: Safrol
safrole in German: Safrol
safrole in Dutch: Safrol
safrole in Polish: Safrol
safrole in Vietnamese: Safrol