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Safrole structure.png
IUPAC name
Other names
Molar mass 162.19 g/mol
Appearance Colorless or slight yellow oil
Odor Sassafras odor
Density 1.096 g/cm3
Melting point 11 °C (52 °F; 284 K)
Boiling point 234.5 °C (454.1 °F; 507.6 K)
0.0121 g/100 ml (25 °C)
Solubility Miscible with chloroform, diethyl ether
Soluble in ethanol
Slightly soluble in propylene glycol
Insoluble in glycerol
Vapor pressure 0.0706 mmHg (25 °C)
Safety data sheet Sigma-Aldrich
Flash point 97 °C (207 °F; 370 K)
Related compounds
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Safrole is a fragrant organic compound found in a variety of plants. It was one of the principal ingredients of old-fashioned root beer prior to studies that deemed it carcinogenic. It is found in small amounts in cinnamon, nutmeg, and black pepper, but is most notably obtained from sassafrass.



Safrole is a precursor to a variety of different compounds with a variety of uses. Refluxing safrole with a proper catalyst such as potassium hydroxide or calcium oxide isomerizes it to both forms of isosafrole, which can be used as a precursor to the pleasant-smelling compound piperonal, a component of many fragrances. Safrole has historically been used as a flavoring agent for root beer and a fragrance, though conflicting claims of carcinogenicity have made it all but disappear from use for this, though many dedicated enthusiasts still produce their own root beer or sassafrass tea containing it. Finally, safrole is used illegally as a precursor to the stimulant drug MDMA (Ecstasy), and thus it may be unwise to possess large amounts of it without a clearly documented purpose for it.


Pure safrole is a clear, oily liquid that is somewhat volatile, but samples derived from natural sources may have a yellowish coloration. Safrole has a very unique and complex smell, being described as similar to root beer, anise, licorice, and various candies, formerly making it a popular candidate for many fragrances and flavoring agents. Modern root beer attempts to imitate the taste and smell of safrole, in part using methyl salicylate, though the majority of the other ingredients of root beer remain the same today.


Safrole is not likely to be available to the public in pure or otherwise usable form, due to its use in illicit drug manufacture. Commercial sassafrass oil used for fragrances or food have no longer contain safrole. However, some small home-brew stores may have sassafrass roots for the purpose of producing root beer in stock, allowing one to derive it from them.


Safrole is most easily extracted from the roots of sassafrass, a deciduous plant or tree which commonly grows in well-shaded areas in the Eastern half of the United States. The essential oil steam-distilled from the bark of these roots is mostly composed of safrole, and can be further purified by fractional distillation. The roots used for this need to be fresh, as the volatile oils inside will eventually diffuse into the air as they dry.

Alternatively, somewhat long syntheses exist for the production of safrole or isosafrole from catechol, eugenol, or vanillin.


  • Homemade root beer or sassafrass tea (see the safety section, as safrole has been classified as carcinogenic by the FDA and is assumed to be so by other international organizations).
  • Use safrole as a fragrance or as a precursor to other fragrances, such as piperonal.



Safrole has been found to be carcinogenic when consumed in large amounts by rats. Despite this, many enthusiasts of old-fashioned beverages (including root beer) that contain safrole continue to produce and consume these beverages. There is not conclusive evidence on whether or not these small amounts are safe to consume or not.

Possession of synthesis-worthy amounts of safrole may present a very serious legal problem, as it is used by some to illegally manufacture MDMA (ecstasy). A permit is required to exchange safrole in any significant amount.


Should not be stored for long periods of time due to its legal status, unless you have a permit.


Can be poured down the drain, though it's best to oxidize it to less harmful compounds before doing that.


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