February 11, 2019
This week I might be a way to your heart.
What molecule am I?
Image of Isovaleraldehyde

Isovaleraldehyde, formally 3-methylbutanal, is a pungent liquid that occurs in natural oils such as orange, lemon, peppermint, and eucalyptus. It is also found in processed foods such as beer, cheese, and chocolate. Its odor has been described variously from “apple-like” to “suffocating”.

In addition to its natural sources, isovaleraldehyde can be synthesized in several ways, including

  • the oxidation of isoamyl alcohol with Na2Cr2O7 and H2SO4,
  • the hydroformylation of isobutene,
  • the isomerization of 3-methyl-3-butene-1-ol catalyzed by CuO–ZnO, and
  • the reaction between isobutene and formaldehyde.

Isovaleraldehyde’s strong aroma makes it useful (in small amounts) as a perfume component. So . . . perfume, chocolate, and beer . . . what else could you possibly need for Valentine’s Day?

Isovaleraldehyde hazard information

GHS classification*: flammable liquids, category 2
H225—Highly flammable liquid and vaporChemical Safety Warning
GHS classification: skin sensitization, category 1
H317—May cause an allergic skin reactionChemical Safety Warning
GHS classification: serious eye damage/eye irritation, category 2A
H319—Causes serious eye irritationChemical Safety Warning
GHS classification: specific target organ toxicity, single exposure, respiratory tract irritation, category 3
H335—May cause respiratory irritationChemical Safety Warning
GHS classification: hazardous to the aquatic environment, long-term hazard, category 2
H411—Toxic to aquatic life with long-lasting effectsChemical Safety Warning

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

Isovaleraldehyde fast facts

CAS Reg. No.590-86-3
Empirical formulaC5H10O
Molar mass86.13 g/mol
AppearanceColorless liquid
Boiling point92–93 ºC
Water solubility1.4–20 g/La

aConflicting data in literature

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Learn more about this molecule from CAS, the most authoritative and comprehensive source for chemical information.

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