2-Methylbutanal

What 2-Methylbutanal smells like

Bedoukian, as quoted by The Good Scents Company, describes 2-methylbutanal as a very volatile, cocoa- or coffee-like material used for lift in woody and cocoa top notes. ChemicalBook lists musty, cocoa, phenolic, coffee, nutty, malty and fermented notes and calls the neat material powerful and choking; Flavornet lists cocoa and almond. PubChem links it to natural-product databases.

Leading note

Cocoa

Clear facets

Coffee

Supporting facets

Malty, nutty

Character

Volatile, diffusive

• cocoa
• coffee
• malty
• nutty

What makes 2-Methylbutanal distinctive

A cocoa note that lifts: volatile enough to work at the very top.

How 2-Methylbutanal is used

Used in traces for lift in cocoa, coffee and woody top notes.

Typical role: modifier (used in small amounts to change the character of a blend).

How 2-Methylbutanal differs from similar materials

2-Ethyl-3,5(6)-dimethylpyrazine

2-Ethyl-3,5(6)-dimethylpyrazine is a heavier toasted nut with a chocolate edge; 2-methylbutanal is a volatile, malty cocoa aldehyde that works at the very top.

Each difference compares the published descriptions of the two materials. Smell varies with grade, supplier and dilution; compare them side by side on blotters before substituting one for another.

Formulation considerations

Very volatile; handle diluted.

Identity and classification

Type

Aroma chemical

Origin

Occurs in nature

Odour family

Gourmand

Note position

Top note

Physical form at room temperature

Liquid

Also known as

2-Methylbutyraldehyde

CAS number

96-17-3

Molecular formula

C5H10O

Molecular weight

86.13 g/mol

IUPAC name

2-methylbutanal

The CAS number, formula and molecular weight are taken from PubChem compound 7284, whose own record lists this CAS number; checked 24 October 2026.

Safety and compliance

Hazard classification of the neat substance, as PubChem summarises it, read 26 October 2026. Companies notifying the ECHA C&L Inventory classify it (1,820 reports): H335 may cause respiratory irritation (84.5% of reports); H317 may cause an allergic skin reaction (84.3% of reports); H411 toxic to aquatic life with long lasting effects (84.2% of reports). A skin sensitiser classification concerns handling the neat material and the dose in a finished product; the IFRA Standards, where they apply, set the limits. Unless it is harmonised, this is the notifiers' own classification, not a binding one.

This page is general information, not a safety assessment or a specification. Confirm identity, composition, IFRA status and allergen content from your supplier's documents for the lot you hold.

Materials it works with

• Cacao Absolute

  Absolute · Gourmand — chocolate, cocoa, roasted, bitter

• Coffee Absolute

  Absolute · Gourmand — roasted, coffee, smoky, bitter

• 2,3,5-Trimethylpyrazine

  Aroma chemical · Gourmand — roasted, nutty, cocoa, earthy

Used in formulas and accords

Used in 2 published formulas

2-Methylbutanal is an ingredient in 1 perfume formula and 1 accord in the Formula & Accord Library.

Community formulas

• Chocolate Accord

  Community Formula · Accord · listed as “2-Methyl Butyraldehyde 1%”, at 1%

RUŌOD House Originals

Original compositions by RUŌOD House.

• Cocoa Moss

  RUŌOD House Original · listed as “2-Methylbutanal 1% DPG”, at 1% in DPG

Further reading

• Building a Gourmand Accord: Vanilla, Caramel and Beyond

  The materials of gourmand perfume — vanillin, ethyl maltol, coumarin, lactones, roasted notes — how to keep them wearable, and color and crystal problems.

Questions about 2-Methylbutanal

Sources

• PubChem — compound 7284, checked 24 October 2026.
• PubChem — GHS classification (the ECHA C&L Inventory notifications and any harmonised EU entry), read 26 October 2026.
• The Good Scents Company — 2-methyl butyraldehyde — odour database.
• ChemicalBook — 96-17-3 — odour database.
• Flavornet — 96-17-3 — odour database.
• Olfactory profile: the RUŌOD Lab team's synthesis of the published descriptions above, reviewed 26 October 2026. Evidence: more than one published description. Classification and the short description: revision 1. Descriptions of odour are judgement, not measurement.