15678

Boric anhydride

puriss. p.a., ≥98% (T)

• Synonym(s): Boron trioxide
• Empirical Formula (Hill Notation): B₂O₃
• CAS Number: 1303-86-2
• Molecular Weight: 69.62
• EC Number: 215-125-8
• MDL number: MFCD00011315
• UNSPSC Code: 12352300
• PubChem Substance ID: 57647516
• NACRES: NA.21

Properties

• vapor density: >1 (vs air)
• Quality Level: 100
• grade: puriss. p.a.
• Assay: ≥98% (T)
• form: solid
• loss: ≤3% loss on ignition, 900 °C
• mp: 450 °C (lit.)
• density: 2.46 g/mL at 25 °C (lit.)
• anion traces: chloride (Cl^-): ≤20 mg/kg; sulfate (SO₄^2-): ≤50 mg/kg
• cation traces: Ag: ≤5 mg/kg; Al: ≤50 mg/kg; Ba: ≤5 mg/kg; Bi: ≤5 mg/kg; Ca: ≤10 mg/kg; Cd: ≤5 mg/kg; Co: ≤5 mg/kg; Cr: ≤5 mg/kg; Cu: ≤5 mg/kg; Fe: ≤5 mg/kg; K: ≤30 mg/kg; Mg: ≤20 mg/kg; Mn: ≤5 mg/kg; Mo: ≤5 mg/kg; Na: ≤200 mg/kg; Ni: ≤5 mg/kg; Pb: ≤30 mg/kg; Sr: ≤5 mg/kg; Tl: ≤10 mg/kg; Zn: ≤5 mg/kg
• SMILES string: O=BOB=O
• InChI: 1S/B2O3/c3-1-5-2-4
• InChI key: JKWMSGQKBLHBQQ-UHFFFAOYSA-N

Description

General description

Boric anhydride (Boron trioxide) is a colorless glassy hygroscopic mass having rhombic crystals. Its dissolution in water is a highly exothermic reaction and orthoboric acid is formed. It can be prepared by heating boric acid. It is used as flux in metallurgical processes. It has been reported as an inhibitor of crystallization.

Application

Boric anhydride can be used as a boron precursor to synthesize:

• Boron carbon nitride nanosheet (BCN) by thermal condensation reaction with urea and melamine.
• Boron-doped reduced graphene oxide (B-rGO) via a chemical vapor deposition method.

It can also be used as an additive along with pinacol to synthesize 4-alkoxy-5-hydroxy-2-pentenoate derivatives by Pd-catalyzed reaction of α, β-unsaturated γ, δ-epoxy esters with various alcohols.

Other Notes

Reagent for the decomposition of silicates by fusion

Safety Information

• Pictograms: GHS08
• Signal Word: Danger
• Hazard Statements: H360FD
• Precautionary Statements: P201 - P202 - P280 - P308 + P313 - P405 - P501
• Hazard Classifications: Repr. 1B
• Storage Class Code: 6.1D - Non-combustible, acute toxic Cat.3 / toxic hazardous materials or hazardous materials causing chronic effects
• WGK: WGK 1
• Flash Point(F): Not applicable
• Flash Point(C): Not applicable
• Personal Protective Equipment: dust mask type N95 (US), Eyeshields, Gloves