Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Butyryl chloride

Butyryl chloride is a colorless liquid with a pungent acid chloride odor.

CAS 141-75-3 C4H7ClO 106.55 g/mol Danger

01 · Identification

What Butyryl chloride is

Butyryl chloride is a colorless liquid with a pungent acid chloride odor. Its molecular formula is C4H7ClO and its molecular weight is 106.55 g/mol. It boils at 102 °C, melts at -89 °C.

Under the GHS it carries the signal word Danger. It is classed as flammable agents - 3rd degree.

CAS number141-75-3
EC number205-498-5
Index number607-136-00-5
Molecular formulaC4H7ClO
Molecular weight106.55 g/mol
Chemical class Flammable agents - 3rd degree

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to Butyryl chloride
CodeHazard statement
H225 Highly flammable liquid and vapour.
H314 Causes severe skin burns and eye damage.

Precautionary statements: P210, P233, P241, P242, P260, P280, P301, P310, P331, P403

03 · Physical and chemical properties

Butyryl chloride properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Boiling point 102.22 °C (216 °F) at 760 mmHg CAMEO
101.5 °C (214.7 °F) range, midpoint shown HSDB
Melting point -89 °C (-128.2 °F) HSDB
-88.89 °C (-128 °F) CAMEO
Density 1.0263 g/cm³ at 20.6 °C HSDB
1.0277 g/cm³ at 20 °C CAMEO
Solubility Reaction (NTP, 1992) CAMEO
Dissolves slowly with decomposition in water decomposes HSDB
Dissolves slowly with decomposition in alcohol; miscible with ether decomposes HSDB
Vapor pressure 30 mmHg at 20 °C HSDB
41.7 mmHg at 25 °C HSDB
18.8 mmHg at -2.22 °C CAMEO
Flash point 18 °C (64.4 °F) HSDB
21.67 °C (71 °F) CAMEO
Vapor density 3.67 (air = 1) vapor specific gravity HSDB
Corrosivity Corrosive to metals HSDB

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling Butyryl chloride

Storage conditions

Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Storage class (TRGS 510): Flammable liquids.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompatible materials: Alcohols, oxidizing agents, strong bases.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

BUTYRYL CHLORIDE slowly dissolves in water with decomposition and formation of a weakly acidic solution. May react vigorously or explosively if mixed with diisopropyl ether or other ethers in the presence of trace amounts of metal salts [J. Haz. Mat., 1981, 4, 291].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Butyryl chloride in the storage compatibility matrix →

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