3-vinyl thiophene

3-vinyl thiophene, also known by its synonym 3-ethenylthiophene, is an aromatic sulfur heterocycle with the molecular formula C₆H₆S. This compound appears as a clear liquid exhibiting a chemical or thiophene-like odor profile that may contribute to certain natural flavor or fragrance notes. Its key identifiers include the CAS number 13679-64-6, which facilitates referencing in chemical registries such as PubChem. It belongs to the natural substances and extractives class and can be found in cooked wheat, where it may contribute to aroma. The compound is of interest for its chemical properties and sensory potential but is currently not recommended for use as a flavoring or fragrance ingredient at regulated levels. It is derived mainly through synthetic routes or isolated as a minor volatile constituent in natural matrices containing sulfur heterocycles.

3-vinyl thiophene occurs naturally in cooked wheat, contributing to its characteristic aroma. It is classified under the natural substances and extractives category and represents a sulfur-containing heterocyclic compound with chemical flavor characteristics. Despite its presence in food matrices, authoritative bodies such as IFRA (Global) recommend restricting its use due to insufficient safety data, and it is currently not approved for flavoring or fragrance use. However, it remains of interest for research and potentially specialized applications in chemical synthesis or natural product studies. Its chemical structure offers a reactive vinyl group attached to a thiophene ring, which may be applicable in organic synthesis beyond flavor or fragrance contexts.

3-vinyl thiophene has a molecular weight of approximately 110.18 g/mol and a chemical formula of C₆H₆S. It is a volatile liquid with a boiling point range near 151 to 152°C at standard atmospheric pressure. The compound exhibits a vapor pressure of about 4.624 mmHg at 25°C, indicating moderate volatility under ambient conditions. The estimated log P value is 2.495, suggestive of moderate lipophilicity, which influences its solubility and partitioning behavior in formulations. Solubility is noted as sufficient in alcohol and estimated moderate in water (~521.5 mg/L at 25°C). The flash point is reported at 29°C (converted from 85°F), indicating flammability concerns during handling. These properties shape its handling requirements and potential formulation uses, mainly in non-aqueous systems.

	3-ethenylthiophene
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Pubchem (cid):	10887853
Pubchem (sid):	80251359

(IUPAC):	Atomic Weights of the Elements 2011 (pdf)
Videos:	The Periodic Table of Videos
tgsc:	Atomic Weights use for this web site
(IUPAC):	Periodic Table of the Elements
HMDB (The Human Metabolome Database):	Search
Export Tariff Code:	2934.90.4000
VCF-Online:	VCF Volatile Compounds in Food
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Safety information

Hazards identification
Classification of the substance or mixture
GHS Classification in accordance with 29 CFR 1910 (OSHA HCS)
None found.
GHS Label elements, including precautionary statements
Pictogram
Hazard statement(s)
None found.
Precautionary statement(s)
None found.
Oral/Parenteral Toxicity:
Not determined
Dermal Toxicity:
Not determined
Inhalation Toxicity:
Not determined

Safety in use information

Category:
natural substances and extractives
Recommendation for 3-vinyl thiophene usage levels up to:
	not for fragrance use.
Recommendation for 3-vinyl thiophene flavor usage levels up to:
	not for flavor use.

Safety references

EPI System: View

AIDS Citations:Search

Cancer Citations:Search

Toxicology Citations:Search

EPA ACToR:Toxicology Data

EPA Substance Registry Services (SRS):Registry

Laboratory Chemical Safety Summary :10887853

National Institute of Allergy and Infectious Diseases:Data

3-ethenylthiophene