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

1,2-Benzisothiazol-3(2H)-one

1,2-Benzisothiazol-3(2H)-one is an off-white to yellowish solid.

CAS 2634-33-5 C7H5NOS 151.19 g/mol Danger

01 · Identification

What 1,2-Benzisothiazol-3(2H)-one is

1,2-Benzisothiazol-3(2H)-one is an off-white to yellowish solid. Its molecular formula is C7H5NOS and its molecular weight is 151.19 g/mol. It boils at 328 °C, melts at 157 °C.

Under the GHS it carries the signal word Danger.

CAS number2634-33-5
EC number220-120-9
Index number613-088-00-6
Molecular formulaC7H5NOS
Molecular weight151.19 g/mol

Other names for 1,2-Benzisothiazol-3(2H)-one

  • 1,2-benzisothiazolin-3-one

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 1,2-Benzisothiazol-3(2H)-one
CodeHazard statement
H330 Fatal if inhaled.
H302 Harmful if swallowed.
H315 Causes skin irritation.
H318 Causes serious eye damage.
H317 May cause an allergic skin reaction.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P260, P261, P264, P270, P271, P272, P273, P280, P301, P302, P304, P305, P310, P312, P313, P330, P332, P333, P338, P352, P391, P501

03 · Physical and chemical properties

1,2-Benzisothiazol-3(2H)-one 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 327.6 °C (621.7 °F) HSDB
Melting point 156.6 °C (313.9 °F) HSDB
157.5 °C (315.5 °F) range, midpoint shown HMDB
Density 1.483 g/cm³ at 20 °C HSDB
Solubility In water, 1.1 g/L at 20 °C; 0.938 g/L at 20 °C and pH 4.8; 1.288 g/L at 20 deg and pH 6.7; 1.651 g/L at 20 °C at pH 9.1; 1.198 g/L at 30 °C pH 4.8 at 20 °C HSDB
21.7 [ug/mL] (The mean of the results at pH 7.4) Sanford-Burnham Center for Chemical Genomics
Vapor pressure 0.00000278 mmHg at 25 °C HSDB

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

04 · Handling and storage

Storing and handling 1,2-Benzisothiazol-3(2H)-one

Storage conditions

Conditions for safe storage, including any incompatibilities: Keep container tightly closed in a dry and well-ventilated place. Storage class (TRGS 510): Non Combustible Solids.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompatible materials: Strong oxidizing agents.

Source: Hazardous Substances Data Bank (HSDB)

Planning storage for a mix of chemicals? Check 1,2-Benzisothiazol-3(2H)… in the storage compatibility matrix →

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