4,4'-Difluorobenzophenone

4,4’-Difluorobenzophenone is an organic compound with the formula of (FC₆H₄)₂CO. This colorless solid is commonly used as a precursor to PEEK, or polyetherether ketone, a so-called high performance polymer. Because PEEK is resistant to attack, it is commonly used in carbon fiber coatings and cable insulation.

4,4'-Difluorobenzophenone

Names
Preferred IUPAC name Bis(4-fluorophenyl)methanone
Identifiers
CAS Number	345-92-6 N
3D model (JSmol)	Interactive image
ChemSpider	9206 Y
ECHA InfoCard	100.005.879
EC Number	206-466-3
PubChem CID	9582
UNII	88BNC11B9C
CompTox Dashboard (EPA)	DTXSID30188062
InChI InChI=1S/C13H8F2O/c14-11-5-1-9(2-6-11)13(16)10-3-7-12(15)8-4-10/h1-8H Y Key: LSQARZALBDFYQZ-UHFFFAOYSA-N Y InChI=1/C13H8F2O/c14-11-5-1-9(2-6-11)13(16)10-3-7-12(15)8-4-10/h1-8H Key: LSQARZALBDFYQZ-UHFFFAOYAZ
SMILES O=C(c1ccc(F)cc1)c2ccc(F)cc2
Properties
Chemical formula	C13H8OF2
Molar mass	218.20 g/mol
Appearance	Colorless Solid
Melting point	107.5 to 108.5 °C (225.5 to 227.3 °F; 380.6 to 381.6 K)
Hazards
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H302, H315, H319, H335, H411
Precautionary statements	P261, P264, P270, P271, P273, P280, P301+P312, P302+P352, P304+P340, P305+P351+P338, P312, P321, P330, P332+P313, P337+P313, P362, P391, P403+P233, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Synthesis

4,4’-Difluorobenzophenone is prepared by the acylation of fluorobenzene with p-fluorobenzoyl chloride. The conversion is typically conducted in the presence of an aluminium chloride catalyst in a petroleum ether solvent.^[1]

FC₆H₄C(O)Cl + C₆H₅F → (FC₆H₄)₂CO + HCl

Uses

The polymer PEEK is generated from the reaction of 4,4'-difluorobenzophenone with the salts of 1,4-benzenediol.^[2]

C₆H₄(ONa)₂ + (FC₆H₄)₂CO → 1/n[(C₆H₄O₂)(C₁₃H₈O)]_n + 2 NaF