Cyclopentene
Cyclopentene (CAS: 142-29-0), a cyclic alkene with the formula C5H8 and a molecular weight of 68.12 g/mol, is a volatile organic compound. It serves as a valuable building block in organic synthesis and chemical research. Its reactivity as an alkene makes it useful for various chemical transformations, including polymerisation and addition reactions. Cyclopentene is supplied by Tech Serve Solutions for laboratory and industrial applications requiring a foundational cyclic olefin.

Organic Synthesis Intermediate
Cyclopentene is utilised as a fundamental building block in the synthesis of more complex organic molecules. Its cyclic structure and alkene functionality allow for a variety of addition and functionalisation reactions crucial in research and development.
Monomer for Polymerisation
This cyclic olefin can participate in ring-opening metathesis polymerisation (ROMP) or other polymerisation techniques to form specialty polymers. These polymers may find applications in materials science or advanced chemical formulations.
Research and Development
As a reactive cyclic alkene, cyclopentene is employed in academic and industrial research laboratories for exploring new synthetic pathways and reaction mechanisms. It is a key reagent for studying alkene chemistry.
| Molecular weight | 68.12 |
|---|---|
| Empirical formula | C5H8 |
| Assay | 96% |
| Boiling point | 44-46 °C(lit.) |
| Density | 0.771 g/mL at 25 °C(lit.) |
| Refractive index | n20/D 1.421(lit.) |
| Vapour pressure | 20.89 psi (55 °C)6.11 psi (20 °C) |
| Melting point | −135 °C(lit.) |
| Autoignition temp | 743 °F |
| Storage temperature | 2-8°C |



Hazard statements
- H225Highly flammable liquid and vapour
- H302Harmful if swallowed
- H304May be fatal if swallowed and enters airways
- H315Causes skin irritation
Precautionary statements
- P210Keep away from heat, sparks and open flames. No smoking
- P280Wear protective gloves, clothing and eye/face protection
- P301IF SWALLOWED
- P331Do NOT induce vomiting
| Protective equipment | Eyeshields, Faceshields, full-face respirator (US), Gloves, multi-purpose combination respirator cartridge (US) |
|---|---|
| Flash point | -34 °C / -29.2 °F |
| Transport (UN / ADR) | UN 2246 3 / PGII |
| Water hazard class (WGK, DE) | 3 |
| Hazard codes (EU) | F,Xn |
| Risk statements (R) | 11-21/22-38-65 |
| Safety statements (S) | 9-16-26-33-36-62 |
Hazard information is provided for guidance. Always consult the product Safety Data Sheet (SDS), available on request, before handling.
Documentation
Every batch ships with a Certificate of Analysis covering assay, identity and purity; the grade is confirmed against your enquiry. Safety Data Sheets and technical data sheets are available on request.
Supply & logistics
Samples for technical evaluation; bulk MOQ by grade and packaging. In-stock material ships in 7–10 working days, worldwide, with full export documentation.
What is Cyclopentene used for?
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Cyclopentene is primarily used as a building block in organic synthesis, as a monomer for polymerisation, and in chemical research and development due to its reactive cyclic alkene structure.
What is the CAS number and formula for Cyclopentene?
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The CAS number for Cyclopentene is 142-29-0, and its chemical formula is C5H8.
What grade and purity does Tech Serve Solutions supply?
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Tech Serve Solutions supplies Cyclopentene with a minimum assay of 96%. This product is intended for research and industrial use, and TSS does not represent it as USP, BP, or EP grade.
How should Cyclopentene be handled safely?
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Cyclopentene is highly flammable and can be harmful if swallowed, inhaled, or absorbed through the skin. It is also a skin and respiratory irritant. Handling requires strict adherence to safety protocols, including the use of appropriate personal protective equipment such as gloves, safety glasses, and respiratory protection in a well-ventilated area. Refer to the Safety Data Sheet (SDS) for full details.
Is Cyclopentene a controlled substance?
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The provided data does not indicate that Cyclopentene is a controlled substance. However, users should always verify local regulations.
How is Cyclopentene packed, shipped, and exported?
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Cyclopentene is packed in accordance with UN 2246 Class 3 regulations for flammable liquids, typically in robust containers suitable for international shipping. Tech Serve Solutions is experienced in exporting chemicals globally.
How can I request a sample or quote for Cyclopentene?
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To request a sample or a quotation for Cyclopentene, please contact the Tech Serve Solutions sales team through our website or by phone, providing your specific requirements and shipping details.
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