1-(3-Chlorophenyl)-3-methyl-2-pyrazolin-5-one
1-(3-Chlorophenyl)-3-methyl-2-pyrazolin-5-one (CAS 90-31-3; C10H9ClN2O; molar mass 208.64 g/mol) is a halogenated pyrazol-5-one (pyrazolone) building block, supplied as a crystalline solid melting at about 128-131 °C. The reactive methylene and ring N-H, together with the meta-chlorophenyl substituent, make it a versatile heterocyclic intermediate in fine-chemical and research synthesis. Tech Serve Solutions supplies it at 97% assay to laboratory and manufacturing customers worldwide.
- Synonyms
- 1-(3-Chlorophenyl)-3-methyl-2-pyrazolin-5-one1-(3-Chlorophenyl)-3-methyl-5-pyrazolone3-Methyl-1-(3-chlorophenyl)-2-pyrazolin-5-one1-(3-Chlorophenyl)-3-methylpyrazol-5(4H)-one5-Methyl-2-(3-chlorophenyl)-2,4-dihydro-3H-pyrazol-3-oneCAS 90-31-3
Heterocyclic building block
Serves as a pyrazol-5-one scaffold for the construction of more complex pyrazole and fused heterocyclic systems. The active methylene group adjacent to the carbonyl readily undergoes condensation, coupling and substitution reactions.
Pharmaceutical and agrochemical intermediate
Used in research and process chemistry as an intermediate toward biologically active pyrazolone derivatives. The meta-chloro aryl group provides a defined handle for further functionalisation.
Dye and pigment chemistry
Pyrazol-5-ones of this type are established coupling components in the preparation of azo dyes and related coloured compounds, where the reactive methylene position participates in coupling reactions.
Chelating and coordination ligands
The pyrazolone framework can be elaborated into ligands that coordinate metal ions, supporting studies in coordination chemistry and analytical applications.
Laboratory reagent and reference material
Supplied at 97% assay for use as a reagent and characterised starting material in method development, structure-activity studies and small-scale synthesis.
| Molecular weight | 208.64 |
|---|---|
| Empirical formula | C10H9ClN2O |
| Assay | 97% |
| Melting point | 128-131 °C(lit.) |
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 1-(3-Chlorophenyl)-3-methyl-2-pyrazolin-5-one used for?
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It is used mainly as a heterocyclic building block and synthetic intermediate. The pyrazol-5-one ring, its reactive methylene group and the meta-chlorophenyl substituent make it useful in the synthesis of pyrazole derivatives, azo dyes and coordination ligands, and as a laboratory reagent.
What is the CAS number and molecular formula of 1-(3-Chlorophenyl)-3-methyl-2-pyrazolin-5-one?
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The CAS number is 90-31-3 and the molecular formula is C10H9ClN2O, with a molecular weight of 208.64 g/mol. The EC number is 201-984-6 and the MDL number is MFCD00020750. It is a crystalline solid melting at approximately 128-131 °C.
What grade and purity does Tech Serve Solutions supply?
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Tech Serve Solutions supplies 1-(3-Chlorophenyl)-3-methyl-2-pyrazolin-5-one at a typical assay of 97% as a technical/research-grade reagent. We do not represent it as USP, BP or EP pharmacopoeial grade. A certificate of analysis is provided with each batch, and specifications can be confirmed at the time of enquiry.
How should 1-(3-Chlorophenyl)-3-methyl-2-pyrazolin-5-one be handled and stored?
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Handle it as a laboratory chemical using good practice: wear suitable gloves, eye protection and a lab coat, avoid generating dust, and work with adequate ventilation. Store the closed container in a cool, dry, well-ventilated place away from incompatible materials. It is classed under German Water Hazard Class WGK 2, so prevent release to drains, soil and watercourses. Always consult the current Safety Data Sheet before use.
How is 1-(3-Chlorophenyl)-3-methyl-2-pyrazolin-5-one packed, shipped and exported?
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It is packed as a solid in appropriately sealed and labelled containers, with pack sizes from research quantities to bulk to suit your requirement. Tech Serve Solutions arranges compliant documentation and export shipping worldwide, with packaging and labelling prepared in line with applicable transport regulations.
How do I request a sample or quote from Tech Serve Solutions?
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Contact Tech Serve Solutions with the product name or CAS number 90-31-3, the quantity and grade you need, and your destination. We will confirm availability, specifications and lead time, and can provide a sample or a formal quotation for laboratory or bulk supply.
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