What molecule am I?

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 | ![]() |
GHS classification: skin corrosion/irritation, category 2 | |
H315—Causes skin irritation | ![]() |
GHS classification: skin sensitization, category 1 | |
H317—May cause an allergic skin reaction** | ![]() |
GHS classification: serious eye damage/eye irritation, category 2A | |
H319—Causes serious eye irritation** | ![]() |
GHS classification: specific target organ toxicity, single exposure; respiratory tract irritation, category 3 | |
H335—May cause respiratory irritation | ![]() |
*Globally Harmonized System of Classification and Labeling of Chemicals. Explanation of pictograms.
trans-Cinnamaldehyde
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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