Following is the structure of 2',3',4',5'-Tertafluoroacetophenone (CAS NO.66286-21-3):
                   
Empirical Formula: C₈H₄F₄O
Molecular Weight: 192.1104 g/mol
Molar Refractivity: 36.25 cm³
Molar Volume: 137.8 cm³
Density: 1.394 g/cm³
Flash Point: 76 °C
Index of Refraction: 1.439
Surface Tension: 29.4 dyne/cm
Enthalpy of Vaporization: 42.31 kJ/mol
Boiling Point: 186.9 °C at 760 mmHg
Vapour Pressure: 0.649 mmHg at 25 °C
Appearance: Clear colourless to light yellow liquid
SMILES: Fc1c(cc(F)c(F)c1F)C(=O)C
InChI: InChI=1/C8H4F4O/c1-3(13)4-2-5(9)7(11)8(12)6(4)10/h2H,1H3
InChIKey: JYKCLBMVRLLJCI-UHFFFAOYAT

Hazard Codes: Xi
Risk Statements 36/37/38
R36/37/38:Irritating to eyes, respiratory system and skin.
Safety Statements 23-26-28-36
S23:Do not breathe vapour.
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.
S28:After contact with skin, wash immediately with plenty of soap-suds.
S36:Wear suitable protective clothing.
WGK Germany: 3

 2',3',4',5'-Tertafluoroacetophenone , its cas register number is 66286-21-3. It also can be called 1-(2,3,4,5-Tetrafluorophenyl)ethanone ; Ethanone, 1-(2,3,4,5-tetrafluorophenyl)- ; m-Fluorotrifluoroacetophenone ; and p-Fluorotrifluoroacetophenone .