1-Methyl-1H-pyrazole-5-carboxaldehyde
1-Methyl-1H-pyrazole-5-carboxaldehyde (CAS: 27258-33-9), with molecular formula C5H6N2O and a molecular weight of 110.11 g/mol, is a heterocyclic aldehyde. This compound serves as a valuable intermediate and building block in organic synthesis, particularly within the pharmaceutical and fine chemical industries. Its pyrazole core and aldehyde functionality allow for diverse chemical transformations, making it a key component in the development of novel molecules.
- IUPAC
- 1-Methylpyrazole-5-carbaldehyde,2-Methyl-2H-pyrazole-3-carbaldehyde

Pharmaceutical Intermediates
Utilised in the synthesis of active pharmaceutical ingredients (APIs) and drug discovery programmes. Its structure is incorporated into various therapeutic agents.
Organic Synthesis Building Block
Serves as a versatile synthon for constructing complex organic molecules. The aldehyde group readily undergoes reactions such as condensation, oxidation, and reduction.
Agrochemical Research
Investigated for potential applications in the development of novel pesticides and herbicides, owing to its heterocyclic nature.
Material Science
Can be employed in the creation of specialised polymers or functional materials where its unique structural features are advantageous.
| Molecular weight | 110.11 |
|---|---|
| Empirical formula | C5H6N2O |
| Assay | 96% |
| Density | 1.118 g/mL at 25 °C |
| Refractive index | n20/D 1.521 |

Hazard statements
- H302Harmful if swallowed
- H315Causes skin irritation
- H317May cause an allergic skin reaction
- H319Causes serious eye irritation
- H335May cause respiratory irritation
Precautionary statements
- P261Avoid breathing dust, fume, gas or vapours
- P280Wear protective gloves, clothing and eye/face protection
- P305IF IN EYES
| Flash point | 66 °C / 150.8 °F |
|---|---|
| Transport (UN / ADR) | NA 1993 / PGIII |
| Water hazard class (WGK, DE) | 3 |
| Hazard codes (EU) | Xn |
| Risk statements (R) | 22-36/37/38 |
| Safety statements (S) | 26-36/37/39 |
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 1-Methyl-1H-pyrazole-5-carboxaldehyde used for?
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1-Methyl-1H-pyrazole-5-carboxaldehyde is primarily used as a building block in organic synthesis, particularly for pharmaceutical intermediates and in chemical research.
What are the CAS number and formula for 1-Methyl-1H-pyrazole-5-carboxaldehyde?
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The CAS number is 27258-33-9 and the molecular formula is C5H6N2O.
What grade and purity does Tech Serve Solutions supply?
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Tech Serve Solutions supplies 1-Methyl-1H-pyrazole-5-carboxaldehyde with an assay of 96%. TSS does not represent this product as USP, BP, or EP grade.
What are the main safety hazards associated with this chemical?
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This compound is a Warning. It is harmful if swallowed (H302), causes skin irritation (H315), may cause an allergic skin reaction (H317), causes serious eye irritation (H319), and may cause respiratory irritation (H335).
How is 1-Methyl-1H-pyrazole-5-carboxaldehyde shipped?
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As a global supplier and exporter, Tech Serve Solutions ensures appropriate packaging and documentation for international shipment of chemicals like 1-Methyl-1H-pyrazole-5-carboxaldehyde.
How can I request a quote or sample?
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Please contact our sales team or use the online enquiry form to request a quote or sample of 1-Methyl-1H-pyrazole-5-carboxaldehyde.
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