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

4-Chlorophenyl Isocyanate

4-Chlorophenyl Isocyanate is colorless to slightly yellow liquid or crystals.

CAS 104-12-1 C7H4ClNO 153.56 g/mol Danger

01 · Identification

What 4-Chlorophenyl Isocyanate is

4-Chlorophenyl Isocyanate is colorless to slightly yellow liquid or crystals. Its molecular formula is C7H4ClNO and its molecular weight is 153.56 g/mol. It boils at 204 °C, melts at 31.3 °C, is soluble in water.

Under the GHS it carries the signal word Danger.

CAS number104-12-1
EC number203-176-9
Index number615-044-00-1
Molecular formulaC7H4ClNO
Molecular weight153.56 g/mol

Other names for 4-Chlorophenyl Isocyanate

  • 4-chlorophenylisocyanate

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 4-Chlorophenyl Isocyanate
CodeHazard statement
H330 Fatal if inhaled.
H302 Harmful if swallowed.
H335 May cause respiratory irritation.
H315 Causes skin irritation.
H318 Causes serious eye damage.
H334 May cause allergy or asthma symptoms or breathing difficulties if inhaled.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P260, P264, P270, P271, P273, P280, P301, P302, P304, P305, P310, P312, P313, P330, P332, P338, P352, P391, P501, P201, P261, P284, P340, P342, P311

03 · Physical and chemical properties

4-Chlorophenyl Isocyanate 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 204 °C (399.2 °F) HSDB
116 °C (240.8 °F) at 45 mmHg (reduced pressure) HSDB
Melting point 31.3 °C (88.3 °F) HSDB
Density 1.25 g/cm³ at 40 °C HSDB
Solubility Soluble in organic solvents HSDB
Vapor pressure 95.4 mmHg at 20 °C HSDB
19.4 mmHg at 25 °C, extrapolated HSDB
95.4 mmHg Haz-Map
Flash point 110 °C (230 °F) HSDB
Lower explosive limit (LEL) Can explode on distillation. HSDB

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

04 · Handling and storage

Storing and handling 4-Chlorophenyl Isocyanate

Storage conditions

Isocyanates are transported in railroad tank cars, tank trucks, tanks in ships, containers, and drums. They are stored in steel tanks and processed in steel equipment. For long-term storage stainless steel is recommended. To avoid contamination by atmospheric moisture, a dry air or inert gas blanket is essential. /Isocyanates/

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Isocyanates and thioisocyanates are incompatible with many classes of compounds, reacting exothermically to release toxic gases. Reactions with amines, aldehydes, alcohols, alkali metals, ketones, mercaptans, strong oxidizers, hydrides, phenols, and peroxides can cause vigorous releases of heat. Acids and bases initiate polymerization reactions in these materials. Some isocyanates react with water to form amines and liberate carbon dioxide. Base-catalysed reactions of isocyanates with alcohols should be carried out in inert solvents. Such reactions in the absence of solvents often occur with explosive violence, [Wischmeyer(1969)].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 4-Chlorophenyl Isocyanate in the storage compatibility matrix →

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