Molecular Structure of 3-Fluorophthalic anhydride (CAS NO.652-39-1):

IUPAC Name:4-Fluoro-2-benzofuran-1,3-dione
Molecular Formula: C₈H₃FO₃
Molecular Weight: 166.106023 g/mol
EINECS:211-491-8
Melting Point: 159-163 °C
Molar Refractivity: 35.67 cm³
Sensitive: Moisture
Density: 1.555 g/cm³
Flash Point: 132.8 °C
Molar Volume: 106.7 cm³
Polarizability: 14.14 10^-24cm³
Enthalpy of Vaporization: 54.35 kJ/mol
Boiling Point: 303.3 °C at 760 mmHg
Vapour Pressure: 0.000941 mmHg at 25 °C
Water Solubility: 740 mg/L at 25 °C
Appearance of 3-Fluorophthalic anhydride (CAS NO.652-39-1): white to off-white crystalline powder
Categories of 3-Fluorophthalic Anhydride(652-39-1): Phthalic Acids, Esters and Derivatives; Carbonyl Compounds; Carboxylic Acid Anhydrides; Organic Building Blocks
Canonical SMILES: C1=CC2=C(C(=C1)F)C(=O)OC2=O
InChI: InChI=1S/C8H3FO3/c9-5-3-1-2-4-6(5)8(11)12-7(4)10/h1-3H
InChIKey: WWJAZKZLSDRAIV-UHFFFAOYSA-N

3-Fluorophthalic anhydride (CAS NO.652-39-1) hasn't been listed as a carcinogen by ACGIH, IARC, NTP, or CA Prop 65.

Hazard Codes:Xn,Xi
Hazard Note:Irritant
Risk Statements:42/43-36/37/38-22
42/43:May cause sensitization by inhalation and skin contact
36/37/38:Irritating to eyes, respiratory system and skin
22:Harmful if swallowed
Safety Statements:45-36/37/39-26-36
45:In case of accident or if you feel unwell, seek medical advice immediately (show label where possible)
36/37/39:Wear suitable protective clothing, gloves and eye/face protection
26:In case of contact with eyes, rinse immediately with plenty of water and seek medical advice
36:Wear suitable protective clothing

 3-Fluorophthalic anhydride , its cas register number 652-39-1. It also can be called 1,3-isobenzofurandione, 4-fluoro- ; 4-Fluor-2-benzofuran-1,3-dion ; 4-Fluoro-2-benzofuran-1,3-dione ; and 4-Fluoro-2-benzofurane-1,3-dione .
 3-Fluorophthalic anhydride (CAS NO.652-39-1) is hazardous, so the first aid measures and others should be known. Such as: When on the skin: first, should flush skin with plenty of water immediately for at least 15 minutes while removing contaminated clothing. Secondly, get medical aid. Or in the eyes: Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Then get medical aid soon. While, it's inhaled: Remove from exposure and move to fresh air immediately. Give artificial respiration while not breathing. When breathing is difficult, give oxygen. And as soon as to get medical aid. Then you have the ingesting of the product : Wash mouth out with water, and get medical aid immediately. 
 3-Fluorophthalic anhydride (CAS NO.652-39-1) could be stable under normal temperatures and pressures. It is Moisture sensitive. It should avoid the condition like incompatible materials, exposure to moist air or water. It is not compatible with strong oxidizing agents. And also prevent it to broken down into hazardous decomposition products: Carbon monoxide, carbon dioxide, hydrogen fluoride gas. However, its hazardous polymerization has not been reported. In addition, it should be stored in a cool, dry place, or stored in a tightly closed container.