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8.00653

Sigma-Aldrich

Selenium dioxide

(sublimed) for synthesis

Synonym(s):

Selenium dioxide, Selenious anhydride, Selenium(IV) oxide

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About This Item

Empirical Formula (Hill Notation):
O2Se
CAS Number:
7446-08-4
Molecular Weight:
110.96
MDL number:
MFCD00003562
UNSPSC Code:
12352303
EC Index Number:
231-194-7
NACRES:
NA.22

vapor pressure

<1 Pa ( 20 °C)

Quality Level

200

form

crystals

potency

68.1 mg/kg LD50, oral (Rat)

reaction suitability

reagent type: oxidant

pH

2 (20 °C, 10 g/L in H2O)

mp

340 °C

solubility

1353 g/L

density

3.95 g/cm3 at 20 °C

storage temp.

2-30°C

SMILES string

[Se](=O)=O

InChI

1S/O2Se/c1-3-2

InChI key

JPJALAQPGMAKDF-UHFFFAOYSA-N

Application

Selenium dioxide (SeO2) is mainly used to oxidize the activated carbon-bearing positions (α-methylene carbon atoms), particularly at allylic or propargylic sites. The more substituted end of the double bond undergoes oxidation.
It can also be used as an oxidizing reagent to synthesize:
  • Amides by oxidative amidation of aldehydes with amines.
  • Tropone from cycloheptatriene in the presence of potassium dihydrogen phosphate.
  • Acetyltetrahydrobenzofurans by oxidation of conjugated dienones.
  • 9-hydroxy-undec-10-ynoate from methyl undec-10-ynoate.

Analysis Note

Assay (iodometric): ≥ 98.0 %

Signal Word

Danger

Hazard Statements

H301 + H331 - H373 - H410

Hazard Classifications

Acute Tox. 3 Inhalation - Acute Tox. 3 Oral - Aquatic Acute 1 - Aquatic Chronic 1 - STOT RE 2

Storage Class Code

6.1D - Non-combustible, acute toxic Cat.3 / toxic hazardous materials or hazardous materials causing chronic effects

WGK

WGK 2

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Regulatory Listings

Regulatory Listings are mainly provided for chemical products. Only limited information can be provided here for non-chemical products. No entry means none of the components are listed. It is the user’s obligation to ensure the safe and legal use of the product.

PDSCL

Poisonous substance

ISHL Indicated Name

Substances Subject to be Indicated Names

ISHL Notified Names

Substances Subject to be Notified Names

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

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