Diphenyl ether

Diphenyl ether

Names
Preferred IUPAC name 1,1'-Oxydibenzene
Other names Oxydibenzene Diphenyl ether Diphenyl oxide 1,1'-Oxybisbenzene Phenoxybenzene
Identifiers
CAS Number	101-84-8 Y
3D model (Jmol)	Interactive image
ChEBI	CHEBI:39258 Y
ChEMBL	ChEMBL38934 Y
ChemSpider	7302 Y
ECHA InfoCard	100.002.711
UNII	3O695R5M1U Y
InChI InChI=1S/C12H10O/c1-3-7-11(8-4-1)13-12-9-5-2-6-10-12/h1-10H Y Key: USIUVYZYUHIAEV-UHFFFAOYSA-N Y InChI=1/C12H10O/c1-3-7-11(8-4-1)13-12-9-5-2-6-10-12/h1-10H Key: USIUVYZYUHIAEV-UHFFFAOYAV
SMILES O(c1ccccc1)c2ccccc2
Properties
Chemical formula	C12H10O
Molar mass	170.21 g·mol−1
Appearance	Colorless solid or liquid
Odor	geranium-like
Density	1.08 g/cm3 (20°C)
Melting point	25 to 26 °C (77 to 79 °F; 298 to 299 K)
Boiling point	121 °C (250 °F; 394 K) at 1.34 kPa (10.05 mm Hg), 258 °C at 100 kPa (1 bar)
Solubility in water	Insoluble
Vapor pressure	0.02 mmHg (25°C)
Magnetic susceptibility (χ)	-108.1·10−6 cm3/mol
Hazards
Safety data sheet	Aldrich MSDS
NFPA 704	1 2
Flash point	115 °C (239 °F; 388 K)
Explosive limits	0.7%-6.0%
Lethal dose or concentration (LD, LC):
LD50 (median dose)	3370 mg/kg (rat, oral) 4000 mg/kg (rat, oral) 4000 mg/kg (guinea pig, oral)
US health exposure limits (NIOSH):
PEL (Permissible)	TWA 1 ppm (7 mg/m3)
REL (Recommended)	TWA 1 ppm (7 mg/m3)
IDLH (Immediate danger)	100 ppm
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Diphenyl ether is the organic compound with the formula O(C₆H₅)₂. The molecule is subject to reactions typical of other phenyl rings, including hydroxylation, nitration, halogenation, sulfonation, and Friedel–Crafts alkylation or acylation. This simple diaryl ether enjoys a variety of niche applications.

Diphenyl ether and many of its properties were first reported as early as 1901. It is synthesized by a modification of the Williamson ether synthesis, here the reaction of phenol and bromobenzene in the presence of base and a catalytic amount of copper:

Involving similar reactions, diphenyl ether is a significant side product in the high-pressure hydrolysis of chlorobenzene in the production of phenol.

The main application of diphenyl ether is as a eutectic mixture with biphenyl, used as a heat transfer medium. Such a mixture is well-suited for heat transfer applications because of the relatively large temperature range of its liquid state. A eutectic mixture [commercially, Dowtherm A] is 73.5% diphenyl ether (diphenyl oxide) and 26.5% diphenyl (biphenyl).

Diphenyl ether is a starting material in the production of phenoxathiin via the Ferrario reaction. Phenoxathiin is used in polyamide and polyimide production.