Chemistry informtion about  is:
IUPAC Name: (E)-2-bromobut-2-ene
Synonyms: 1-Methyl-1-Propenyl Bromide ; 2-Bromo-2-Butene ; 2-Bromo-Trans-2-Butene ; (E)-2-Bromo-2-Butene ; Cis,Trans-2-Bromo-2-Butene ; Trans-2-Bromo-2-Butene ; 2-Bromo-But-2c-Ene ; 2-Butene, 2-Bromo-, (E)-
MF: C₄H₇Br
MW: 135
EINECS: 236-316-2 
Density: 1.334 g/cm³
Flash Point: 13.6 °C
Boiling Point: 93.9 °C at 760 mmHg
Vapour Pressure: 55.2 mmHg at 25°C 
Enthalpy of Vaporization: 31.98 kJ/mol
Storage temp.: 2-8°C
Following is the molecular structure of  2-Bromo-2-Butene (CAS NO.3017-71-8) is:

Hazard Codes:
F: Flammable
Risk Statements:
R11:Highly flammable.
Safety Statements:
S16:Keep away from sources of ignition.  
S29:Do not empty into drains. 
S33:Take precautionary measures against static discharges. 
S7/9:Keep container tightly closed and in a well-ventilated place.
RIDADR: UN 1993 3/PG 2
WGK Germany: 3
HazardClass: 3.1
PackingGroup: II

General description about 2-Bromo-2-Butene (CAS NO.3017-71-8) .
First Aid Measures:
Eyes: Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.
Skin: Get medical aid. Flush skin with plenty of water for at least 15 minutes while removing contaminated clothing and shoes. Remove contaminated clothing and shoes.
Ingestion: If victim is conscious and alert, give 2-4 cupfuls of milk or water. Get medical aid immediately. Do NOT induce vomiting. If conscious and alert, rinse mouth and drink 2-4 cupfuls of milk or water.
Inhalation: Get medical aid immediately. Remove from exposure and move to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. 
Handling and Storage:
Handling: Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Keep away from heat, sparks and flame.
Storage: Keep away from heat, sparks, and flame. Keep refrigerated. (Store below 4°C/39°F.) Material darkens in color on storage.