5-Chloro-2-thiophenecarbonitrile
5-Chloro-2-thiophenecarbonitrile (CAS 50478-16-5) is a halogenated thiophene building block with the molecular formula C5H2ClNS and a molar mass of 143.59 g/mol. It is a chlorinated, nitrile-bearing five-membered heteroaromatic in which a reactive chloride and a cyano group flank the thiophene ring, making it a versatile intermediate for chemical synthesis. Tech Serve Solutions supplies it as a 97% research-grade reagent for pharmaceutical, agrochemical and fine-chemical building-block applications.
- IUPAC
- 2-Chloro-5-cyanothiophene
- Synonyms
- 5-Chloro-2-thiophenecarbonitrile2-Chloro-5-cyanothiophene5-Chlorothiophene-2-carbonitrile5-Chloro-2-cyanothiopheneCAS 50478-16-5

Heterocyclic building block
Serves as a halogenated thiophene scaffold in chemical synthesis. The chloro and nitrile substituents provide two complementary handles for elaborating substituted thiophene derivatives.
Pharmaceutical intermediate
Used in medicinal-chemistry programmes as an intermediate towards thiophene-containing active ingredients and candidate molecules. The nitrile group is a common precursor to amines, amidines, tetrazoles and carboxylic acids.
Cross-coupling and substitution chemistry
The ring chloride participates in transition-metal-catalysed cross-coupling and nucleophilic substitution, allowing carbon-carbon and carbon-heteroatom bonds to be installed on the thiophene core.
Agrochemical and specialty synthesis
Applied as a fine-chemical building block in the preparation of thiophene-based structures for agrochemical and specialty-chemical research, where halogenated heterocycles are frequently used motifs.
Laboratory research reagent
Supplied as a reagent for method development and exploratory synthesis in research and development laboratories working with functionalised thiophenes.
| Molecular weight | 143.59 |
|---|---|
| Empirical formula | C5H2ClNS |
| Assay | 97% |
| Boiling point | 208 °C/760 mmHg |
| Density | 1.361 g/mL at 25 °C |
| Refractive index | n20/D 1.587 |


Hazard statements
- H301Toxic if swallowed
- H310Fatal in contact with skin
- H318Causes serious eye damage
- H330Fatal if inhaled
Precautionary statements
- P260Do not breathe dust, fume, gas, mist, vapours or spray
- P280Wear protective gloves, clothing and eye/face protection
- P284Wear respiratory protection
- P302IF ON SKIN
- P305IF IN EYES
- P310Immediately call a POISON CENTER or doctor
| Protective equipment | Eyeshields, Faceshields, full-face respirator (US), Gloves, multi-purpose combination respirator cartridge (US), type ABEK (EN14387) respirator filter |
|---|---|
| Flash point | 95 °C / 203 °F |
| Transport (UN / ADR) | UN 2810 6.1 / PGIII |
| Water hazard class (WGK, DE) | 3 |
| Hazard codes (EU) | T+ |
| Risk statements (R) | 26/27/28-41 |
| Safety statements (S) | 26-28-36/37-39-45 |
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 5-Chloro-2-thiophenecarbonitrile used for?
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It is used mainly as a halogenated thiophene building block and intermediate in chemical synthesis. The reactive chloride and nitrile groups make it useful for preparing substituted thiophene derivatives in pharmaceutical, agrochemical and fine-chemical research. Specific end uses depend on the synthetic route chosen by the user.
What is the CAS number and molecular formula of 5-Chloro-2-thiophenecarbonitrile?
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The CAS number is 50478-16-5 and the molecular formula is C5H2ClNS, with a molecular weight of 143.59 g/mol. Its MDL number is MFCD09265032 and the PubChem Substance ID is 24884194. A common synonym is 2-Chloro-5-cyanothiophene.
What grade and purity does Tech Serve Solutions supply?
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Tech Serve Solutions supplies 5-Chloro-2-thiophenecarbonitrile at a typical assay of 97% as a research/technical-grade reagent. We do not represent it as USP, BP or EP pharmacopoeia grade. A certificate of analysis can be provided on request, and specifications such as assay can be confirmed at the time of enquiry.
What are the safety and handling requirements for 5-Chloro-2-thiophenecarbonitrile?
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This is a hazardous material classified under GHS05 and GHS06 with the signal word Danger. It is toxic if swallowed (H301), fatal in contact with skin (H310), fatal if inhaled (H330) and causes serious eye damage (H318). Handle only with suitable engineering controls and personal protective equipment, including gloves, eye and face protection and appropriate respiratory protection. Always consult the Safety Data Sheet before use.
How is 5-Chloro-2-thiophenecarbonitrile packed, shipped and exported?
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It is packed in suitable sealed laboratory and bulk containers and labelled in line with its GHS classification. For transport it is regulated as UN 2810, Class 6.1, Packing Group III. As a global supplier and exporter, Tech Serve Solutions arranges compliant international dispatch with the required hazardous-goods documentation; pack sizes can be quoted to your requirement.
How do I request a sample or quote?
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Contact Tech Serve Solutions with your required quantity, purity and destination, and our team will respond with availability, lead time and a quotation. Samples and certificates of analysis can be arranged subject to the hazardous-material handling and transport requirements for this product.
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