242845

Acetic anhydride

ACS reagent grade, ≥98.0%, liquid

• Synonym(s): Acetanhydride, Acetic acid anhydride, Acetyl acetate, Acetyl anhydride, Ethanoic anhydride
• Linear Formula: (CH₃CO)₂O
• CAS Number: 108-24-7
• Molecular Weight: 102.09
• NACRES: NA.21
• PubChem Substance ID: 24854587
• UNSPSC Code: 12352100
• EC Number: 203-564-8
• MDL number: MFCD00008705
• Beilstein/REAXYS Number: 385737
• Assay: ≥98.0%
• Form: liquid

Properties

• Product Name: Acetic anhydride, ACS reagent, ≥98.0%
• grade: ACS reagent
• Quality Segment: 200
• vapor density: 3.5 (vs air)
• vapor pressure: 10 mmHg ( 36 °C), 4 mmHg ( 20 °C)
• assay: ≥98.0%
• form: liquid
• autoignition temp.: 629 °F
• expl. lim.: 10.3 %
• impurities: MnO₄^- reducers, passes test
• evapn. residue: ≤0.003%
• refractive index: n20/D 1.390 (lit.)
• bp: 138-140 °C (lit.)
• mp: −73 °C (lit.)
• solubility: H₂O: slightly soluble
• density: 1.08 g/mL (lit.)
• anion traces: chloride (Cl^-): ≤5 ppm, phosphate (PO₄^3-): ≤0.001%, sulfate (SO₄^2-): ≤5 ppm
• cation traces: Fe: ≤5 ppm, heavy metals: ≤2 ppm
• functional group: anhydride, ester
• SMILES string: CC(=O)OC(C)=O
• InChI: 1S/C4H6O3/c1-3(5)7-4(2)6/h1-2H3
• InChI key: WFDIJRYMOXRFFG-UHFFFAOYSA-N

Description

General description

Acetic anhydride is an organic solvent. On dissolution in water it undergoes solvolysis to afford acetic acid. It is widely employed for the acetylation of various alcohols. Wacher process (starting reagent + a ketene) and Knapsack process (starting reagent = acetaldehyde) have been reported for the industrial preparation of acetic anhydride.

Application

Acetic anhydride has been used as one of the reaction components in the preparation of:

• 2-acetylamino-5-aminobenzenesulfonic acid
• 3,3′-bis(sulfonato)-4,4′-bis(chloroacetamido)azobenzene (BSBCA)
• 10-acetoxy-9-nitro-octadecanoic acid, allyl ester
• 9-nitro-oleic acid

It may be used for acetylation of anisole over HBEA zeolite in a batch reactor.

Safety Information

• signalword: Danger
• pictograms: GHS02,GHS06,GHS05
• hcodes: H226,H302,H314,H330
• pcodes: P210 - P280 - P301 + P312 - P303 + P361 + P353 - P304 + P340 + P310 - P305 + P351 + P338
• Hazard Classifications: Acute Tox. 2 Inhalation - Acute Tox. 4 Oral - Eye Dam. 1 - Flam. Liq. 3 - Skin Corr. 1B
• Storage Class: 3 - Flammable liquids
• flash_point_f: 120.2 °F - closed cup
• flash_point_c: 49 °C - closed cup
• ppe: Faceshields, Gloves, Goggles, type ABEK (EN14387) respirator filter