3-Methyl-3-pyrazolin-5-one
Also known as: 3-Methyl-5-pyrazolone, 5-Methyl-2,4-dihydro-3H-pyrazol-3-one, 1,2-Dihydro-3-methyl-5H-pyrazol-5-one, 3-Hydroxy-5-methyl-1H-pyrazole, 3-Methyl-2-pyrazolin-5-one, 3-Methyl-3-pyrazoline-5-one, AKOS B028792, MFCD00010705
3-Methyl-3-pyrazolin-5-one (CAS 4344-87-0) is a compound in the Pharma Intermediates category listed in the Jingsj chemical database. It has the molecular formula C4H6N2O and a molecular weight of 98.103 g/mol. Key properties include a melting point of 223-225 °C(lit.), a boiling point of 309.7 °C at 760 mmHg and a density of 1.3±0.1 g/cm3. It is classified under GHS with signal word Warning and hazard statements H315 — Causes skin irritation, H319 — Causes serious eye irritation and H335 — May cause respiratory irritation. No supplier offers are currently listed; request a quote. Record last updated Aug 21, 2026.
- CAS No.
- 4344-87-0
- Jingsj CID
- J-3802-8
- Molecular Formula
- C4H6N2O
- Molecular Weight
- 98.103 g/mol
- Category
- Pharma Intermediates
- Last updated
- 8/21/2026
No offers for this compound yet.
Request a quotePhysicochemical Properties
| Melting Point | 223-225 °C(lit.) |
|---|---|
| Boiling Point | 309.7 °C at 760 mmHg |
| Density | 1.3±0.1 g/cm3 |
| Exact Mass | 98.048012 |
| PSA | 48.65000 |
| LogP | -1.08 |
| Refractive Index | 1.599 |
GHS Safety & Compliance
- H315 — Causes skin irritation
- H319 — Causes serious eye irritation
- H335 — May cause respiratory irritation
Customs & Trade Information
| HS Code | 2933199090 |
|---|---|
| Summary | 2933199090. other compounds containing an unfused pyrazole ring (whether or not hydrogenated) in the structure. VAT:17.0%. Tax rebate rate:13.0%. . MFN tariff:6.5%. General tariff:20.0% |
Frequently Asked Questions
What is the CAS number of 3-Methyl-3-pyrazolin-5-one?
The CAS number of 3-Methyl-3-pyrazolin-5-one is 4344-87-0.
What are the molecular formula and molecular weight of 3-Methyl-3-pyrazolin-5-one?
3-Methyl-3-pyrazolin-5-one has molecular formula C4H6N2O and molecular weight 98.103 g/mol.
Is 3-Methyl-3-pyrazolin-5-one hazardous?
3-Methyl-3-pyrazolin-5-one has GHS signal word Warning and hazard statements H315 — Causes skin irritation; H319 — Causes serious eye irritation; H335 — May cause respiratory irritation.
What are the upstream and downstream products of 3-Methyl-3-pyrazolin-5-one?
For 3-Methyl-3-pyrazolin-5-one, Upstream Products: Ethyl acetoacetate, Ethyl 2-acetyl-3-hydroxy-2-butenoate, tert-Butyl acetoacetate; Downstream Products: Pyrazothion, 4,4-Dibromo-3-methyl-2-pyrazolin-5-one, Pyruvic acid.
Data compiled from public chemical databases such as PubChem and supplier catalogs; supplier offers are provided by suppliers.
Last updated:
How to cite: Jingsj. "3-Methyl-3-pyrazolin-5-one (CAS 4344-87-0)". Jingsj Chemical Database. https://www.jingsj.com/compound/J-3802-8 (accessed 2026-11-09).
Data for reference only; verify product details with suppliers before purchase.