5-ethynyl-1H-pyrazole
5-Ethynyl-1H-pyrazole (CAS 23486-70-6; molecular formula C5H4N2; molar mass 92.10 g/mol) is a heterocyclic building block that combines a pyrazole ring with a terminal alkyne (ethynyl) group. This bifunctional scaffold is valued in medicinal and synthetic chemistry, where the alkyne serves as a handle for click chemistry and cross-coupling while the pyrazole nitrogen offers further derivatisation. Tech Serve Solutions supplies it as a research-grade reagent for laboratory and process development use.
- Synonyms
- 5-ethynyl-1H-pyrazole3-ethynyl-1H-pyrazole5-ethynylpyrazole3-ethynylpyrazole1H-pyrazole, 5-ethynyl-
Heterocyclic building block
Used as a C3-to-C5 pyrazole building block in chemical synthesis, providing a compact azole core for constructing more elaborate heterocyclic and pharmaceutical intermediates.
Click chemistry and triazole formation
The terminal alkyne participates in copper-catalysed azide-alkyne cycloaddition (CuAAC), allowing pyrazole-bearing 1,2,3-triazoles to be assembled in bioconjugation and discovery chemistry.
Transition-metal cross-coupling
The ethynyl group is a substrate for Sonogashira and related couplings, enabling carbon-carbon bond formation and the extension of the molecular framework in route scouting.
Medicinal chemistry scaffold
Pyrazole alkynes of this type are employed in fragment-based and library synthesis, where the dual reactive sites support rapid analogue generation.
Laboratory research reagent
Supplied for analytical, method-development and exploratory synthesis applications that require a defined, reproducible terminal-alkyne pyrazole.
| Molecular weight | 92.10 |
|---|---|
| Empirical formula | C5H4N2 |
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-ethynyl-1H-pyrazole used for?
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It is used principally as a heterocyclic building block in chemical synthesis. The terminal alkyne enables click chemistry (CuAAC) and Sonogashira-type cross-coupling, while the pyrazole ring provides a versatile core for pharmaceutical intermediates, fragment libraries and medicinal-chemistry research.
What is the CAS number and molecular formula of 5-ethynyl-1H-pyrazole?
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The CAS number is 23486-70-6 and the empirical formula is C5H4N2 (Hill notation), corresponding to a molecular weight of 92.10 g/mol.
What grade and purity does Tech Serve Solutions supply?
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We supply 5-ethynyl-1H-pyrazole as a research/technical-grade building block intended for laboratory and process-development use. It is not represented as a USP, BP or EP pharmacopoeial grade. Batch-specific assay and certificate of analysis details are confirmed at the time of enquiry.
How should 5-ethynyl-1H-pyrazole be handled and stored?
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Handle it as a reactive organic reagent under good laboratory practice: use appropriate PPE, work with adequate ventilation, and keep it away from heat and incompatible materials, since terminal alkynes can be reactive. It carries German Water Hazard Class WGK 3 (strongly hazardous to water), so prevent any release to drains, soil or watercourses. Refer to the current Safety Data Sheet before use.
How is 5-ethynyl-1H-pyrazole packed, shipped and exported?
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It is packed in suitable laboratory-grade containers sized to the order, with appropriate labelling and documentation. As a specialist exporter since 1998, Tech Serve Solutions arranges compliant international shipment with the relevant transport paperwork and Safety Data Sheet.
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, packing options and current documentation. Sample availability is confirmed on a per-enquiry basis.
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