My watch list

Propanoic anhydride

Propanoic anhydride

General
Systematic name	Propanoyl propanoate
Other names	Propionic anhydride
Molecular formula	C₆H₁₀O₃
SMILES	?
Molar mass	130.14 g/mol
Appearance	Clear liquid, with a strong smell similar to vinegar
CAS number	[123-62-6]
Properties
Density and phase	1.015 g/cm³, liquid
Solubility in water	Reacts to give propionic acid
Melting point	-42 °C
Boiling point	167 - 170 °C
Viscosity	1.144 cP at ?°C
Structure
Dipole moment	? D
Hazards
MSDS	External MSDS
Main hazards	flammable
NFPA 704
Flash point	63 °C
R/S statement	R: R34 S: S26-45
RTECS number	UF9100000
Related compounds
Related compounds	Acetic anhydride
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Propanoic anhydride, also called propionic anhydride, is a simple acid anhydride. With the chemical formula (CH₃CH₂CO)₂O, it is a widely used reagent in organic synthesis.

Additional recommended knowledge

What is the Correct Way to Check Repeatability in Balances?

Don't let static charges disrupt your weighing accuracy

Safe Weighing Range Ensures Accurate Results

1 Synthesis
2 Safety
3 Legal Status
4 References

Synthesis

Propionic anhydride has been prepared by dehydration of propionic acid using ketene:^[1]

2 CH₃CH₂CO₂H + CH₂=C=O → (CH₃CH₂CO)₂O + CH₃CO₂H

Safety

Propanoic anhydride is strong smelling and corrosive, and will cause burns on contact with skin. Vapour can burn eyes and lungs.

Legal Status

Due to its potential use as a precursor in the synthesis of fentanyl and fentanyl analogs, propanoic anhydride is regulated by the United States Drug Enforcement Agency as a List I chemical under the Controlled Substances Act.^[2]