Happy Halloween!
October 28, 2019
Strangely, I’m used in candy and pesticides.
What molecule am I?
Image of trans-Cinnamaldehyde

trans-Cinnamaldehyde, as its name suggests, is a natural product that occurs in cinnamon oils. Its cis counterpart is not found in nature; thus, “trans” is often omitted from its name.

As early as the 1830s, chemists reported synthesizing cinnamaldehyde via the aldol condensation of benzaldehyde and acetaldehyde. But the most economical way of producing it is still by steam distilling the bark of trees in the genus Cinnamomum.

Cinnamaldehyde is an important flavoring in foods (e.g., candy and cookies) and an odorant for perfumes. It has also been used to eradicate mosquito larvae and repel adult mosquitoes. Because it exists naturally, it is suitable for organic agriculture.

Now for a different take on cinnamaldehyde. Halloween is almost here, with its ghosts, witches, hobgoblins—and mummies. It turns out that the ancient Egyptians (ca. 2600 BCE) used the bark of cassia trees (Cinnamomum cassia) as an insecticide to help preserve mummies and give them a pleasing aroma.

Happy Halloween to you and your mummy!

trans-Cinnamaldehyde hazard information

GHS classification*: flammable liquids, category 4
H227—Combustible liquid Chemical Safety Warning
GHS classification: skin corrosion/irritation, category 2
H315—Causes skin irritation Chemical Safety Warning
GHS classification: skin sensitization, category 1
H317—May cause an allergic skin reaction** Chemical Safety Warning
GHS classification: serious eye damage/eye irritation, category 2A
H319—Causes serious eye irritation** Chemical Safety Warning
GHS classification: specific target organ toxicity, single exposure; respiratory tract irritation, category 3
H335—May cause respiratory irritation Chemical Safety Warning

*Globally Harmonized System of Classification and Labeling of Chemicals. Explanation of pictograms.

fast facts

CAS Reg. No. 14371-10-9
Empirical formula C9H8O
Molar mass 132.16 g/mol
Appearance Yellow oily liquid
Boiling point 250–253 ºC
Water solubility ≈1.4 g/L
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Learn more about this molecule from CAS, the most authoritative and comprehensive source for chemical information.

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