1. Basic Identification Information

Parameter	English Specification/Value
IUPAC Name	(E)-3-(4-Methoxyphenyl)-2-propenoic acid 2-ethylhexyl ester (also: 2-ethylhexyl 4-methoxycinnamate)
Common Name(s)	Octinoxate; OMC; Ethylhexyl methoxycinnamate; Parsol MCX; Eusolex 2292; Neo Heliopan AV
CAS Registry Number	5466-77-3
EC/EINECS Number	226-775-7
Molecular Formula	C₁₈H₂₆O₃
Molecular Weight	290.40 g/mol
Chemical Class	Cinnamate ester; organic UV-B filter; sunscreen agent; personal care preservative

2. Physicochemical Properties

Property Category	Specific Parameter	Specification/Value
Structural Features	Functional Groups	Methoxy group (-OCH₃); cinnamate ester linkage (-COO-); trans configuration (E-isomer)
Physical Appearance	State & Color	Clear, colorless to pale yellow liquid; very faint, characteristic ester-like odor
	Melting Point	-20 to -18 °C (liquid at room temperature)
	Boiling Point	198–200 °C at 1 mmHg; 350–360 °C at atmospheric pressure (decomposes slightly)
	Density (25 °C)	1.00–1.01 g/cm³
	Refractive Index (25 °C)	1.5350–1.5370