325473

Selenium dioxide

reagent grade, powder, 98%

• Synonym(s): NSC 56753, Selenium oxide
• Linear Formula: SeO₂
• CAS Number: 7446-08-4
• Molecular Weight: 110.96
• EC Number: 231-194-7
• MDL number: MFCD00003562
• UNSPSC Code: 12352303
• PubChem Substance ID: 24859512
• NACRES: NA.22

Properties

• grade: reagent grade
• vapor pressure: 1 mmHg ( 157 °C)
• assay: 98%
• form: powder
• reaction suitability: reagent type: oxidant
• color: off-white to pink
• mp: 315 °C (subl.) (lit.)
• SMILES string: O=[Se]=O
• InChI: 1S/O2Se/c1-3-2
• InChI key: JPJALAQPGMAKDF-UHFFFAOYSA-N

Description

Application

Selenium dioxide (SeO₂) is mainly used to oxidize the α-methylene carbon atoms adjacent to a double bond to form allylic hydroxy derivatives.
Other applications:

• SeO₂ reacts with olefins in the presence of tert-butyl hydrogen peroxide to form allylic alcohols without the formation of rearrangement or dehydration by-products. This reagent system is also useful for the oxidation reactions of acetylenic fatty esters.
• SeO₂ can be used for the oxidation of 1,3,5-cycloheptatriene to form tropone.
• Piperidoindole systems on oxidation with SeO₂ forms either 2-acyl- or 3-acyl-indoles or fully aromatic β-carbolines, depending on the starting material.
• SeO₂ reacts with chlorotrimethylsilane to form selenium oxychloride in situ, which is an effective chlorinating reagent for alcohols. This reagent is a better alternative to thionyl chloride and other chlorinating agents.

Safety Information

• pictograms: GHS06,GHS08,GHS09
• signalword: Danger
• hcodes: H301 + H331,H373,H410
• pcodes: P260 - P264 - P273 - P301 + P310 - P304 + P340 + P311 - P314
• Hazard Classifications: Acute Tox. 3 Inhalation - Acute Tox. 3 Oral - Aquatic Acute 1 - Aquatic Chronic 1 - STOT RE 2
• Storage Class: 6.1C - Combustible acute toxic Cat.3 / toxic compounds or compounds which causing chronic effects
• wgk_germany: WGK 2
• flash_point_f: Not applicable
• flash_point_c: Not applicable
• ppe: Eyeshields, Faceshields, Gloves, type P2 (EN 143) respirator cartridges