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 liquidChemical Safety Warning
GHS classification: skin corrosion/irritation, category 2
H315—Causes skin irritationChemical 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 irritationChemical Safety Warning

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

fast facts

CAS Reg. No.14371-10-9
Empirical formulaC9H8O
Molar mass132.16 g/mol
AppearanceYellow oily liquid
Boiling point250–253 ºC
Water solubility≈1.4 g/L

MOTW update:
November 27, 2023

trans-Cinnamaldehyde1 was the Molecule of the Week for October 28, 2019. A constituent of cinnamon oils, it is an important food flavoring and perfume odorant. Earlier this month, Chen Jin, Zong-yi Wu, Lei Yang, and co-workers at Wenzhou Medical University (China) and Key Laboratory of Orthopedics of Zhejiang Province (Wenzhou) reported that trans-cinnamaldehyde has a beneficial health effect. They found that the compound alleviates bone loss by targeting oxidative stress and mitochondrial damage via the nuclear factor erythroid 2–related factor 2/HO-1 signaling pathway in bone marrow mesenchymal stem cells and ovariectomized mice.

1. CAS Reg. No. 14371-10-9.

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