The Molecular Structure of  2,5-Dichlorothiophene-3-sulfonyl chloride (CAS NO.56946-83-9) is

Cas Register Number: 56946-83-9
Synonyms:  2,5-Dichlorothiophene-3-sulfonyl chloride ; 3-Thiophenesulfonyl chloride, 2,5-dichloro- ; 2,5-Dichlorothiophene-3-Sulphonyl Chloride ; 2,5-Dichlorothiophene-3-sulphonyláchloride
Molecular formula: C₄HCl₃O₂S₂
Molecular weight: 251.5385g/mol 
Product Categories: Thiophene&Benzothiophene;Halogenated Heterocycles;Heterocyclic Building Blocks;Thiophenes;ThiophenesBuilding Blocks 
H bond acceptors: 2
H bond donors: 0
Freely Rotating Bonds: 1
Polar Surface Area: 70.76 Å²
Index of Refraction: 1.607
Molar Refractivity: 48.19 cm³
Molar Volume: 139.4 cm³
Surface Tension: 55.8 dyne/cm
Density: 1.803 g/cm³
Flash Point: 148.9 °C
Enthalpy of Vaporization: 54.19 kJ/mol
Boiling Point: 322.5 °C at 760 mmHg
Vapour Pressure of  2,5-Dichlorothiophene-3-sulfonyl chloride (CAS NO.56946-83-9): 0.000523 mmHg at 25°C

Hazard Codes: C,Xi
Risk Statements: 34 
R34:Causes burns.
Safety Statements: 26-36/37/39-45
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. 
S36/37/39:Wear suitable protective clothing, gloves and eye/face protection. 
S45:In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.)
RIDADR: UN 1760 8/PG 3
WGK Germany: 3
Hazard Note:Irritant
HazardClass: 8
PackingGroup: II