Molecular Structure:

Molecular Formula: C₅H₆O₂
Molecular Weight: 98.0999
IUPAC Name: 3-Methylideneoxolan-2-one
Synonyms of 3-Methylenedihydro-2(3H)-furanone (CAS NO.547-65-9): AI3-63021 ; Dihydro-3-methylene-2(3H)-furanone ; EINECS 208-931-6 ; NSC 205367 ; alpha-Methylene butyrolactone ; alpha-Methylene-gamma-butyrolactone ; 2(3H)-Furanone, dihydro-3-methylene-
CAS NO: 547-65-9
Product Categories: Anti-ulcer agents ; Gastrointestinal Agents 
Index of Refraction: 1.452
Molar Refractivity: 24.54 cm³
Molar Volume: 90.9 cm³
Surface Tension: 29.2 dyne/cm
Density: 1.07 g/cm³
Flash Point: 83.6 °C
Enthalpy of Vaporization: 44.06 kJ/mol
Boiling Point: 204.4 °C at 760 mmHg
Vapour Pressure of 3-Methylenedihydro-2(3H)-furanone (CAS NO.547-65-9): 0.264 mmHg at 25°C

Hazard Codes of 3-Methylenedihydro-2(3H)-furanone (CAS NO.547-65-9): Xn
Risk Statements: 42/43 
R42/43: May cause sensitization by inhalation and skin contact.
Safety Statements: 23-36/37 
S23: Do not breathe vapour. 
S36/37: Wear suitable protective clothing and gloves.
RIDADR: 1993
WGK Germany: 3
F: 1-8-10
HazardClass: 3.2
PackingGroup: III