4,4-Dibromo-3-methyl-2-pyrazolin-5-one
Also known as: 4,4-Dibromo-5-methyl-2,4-dihydro-3H-pyrazol-3-one, 4,4-Dibromo-3-methyl-1H-pyrazol-5(4H)-one, 4,4-Dibromo-3-methyl-1,4-dihydro-pyrazol-5-one, 3-methyl-4,4-dibromo-2-pyrazolin-5-one, 4,4-dibromo-3-methyl-1H-pyrazolin-5-one
4,4-Dibromo-3-methyl-2-pyrazolin-5-one (CAS 33549-66-5) is a compound in the Pharma Intermediates category listed in the Jingsj chemical database. It has the molecular formula C4H4Br2N2O and a molecular weight of 255.89500 g/mol. Key properties include a melting point of 129-132ºC and a density of 2.44g/cm3. No supplier offers are currently listed; request a quote. Record last updated Aug 21, 2026.
- CAS No.
- 33549-66-5
- Jingsj CID
- J-21196-1
- Molecular Formula
- C4H4Br2N2O
- Molecular Weight
- 255.89500 g/mol
- Category
- Pharma Intermediates
- Last updated
- 8/21/2026
No offers for this compound yet.
Request a quotePhysicochemical Properties
| Melting Point | 129-132ºC |
|---|---|
| Density | 2.44g/cm3 |
| Exact Mass | 253.86900 |
| PSA | 41.46000 |
| LogP | 0.74260 |
| Refractive Index | 1.71 |
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 4,4-Dibromo-3-methyl-2-pyrazolin-5-one?
The CAS number of 4,4-Dibromo-3-methyl-2-pyrazolin-5-one is 33549-66-5.
What are the molecular formula and molecular weight of 4,4-Dibromo-3-methyl-2-pyrazolin-5-one?
4,4-Dibromo-3-methyl-2-pyrazolin-5-one has molecular formula C4H4Br2N2O and molecular weight 255.89500 g/mol.
What are the upstream and downstream products of 4,4-Dibromo-3-methyl-2-pyrazolin-5-one?
For 4,4-Dibromo-3-methyl-2-pyrazolin-5-one, Upstream Products: 3-Methyl-5-pyrazolone, 3-Methyl-3-pyrazolin-5-one, 5-methyl-3H-pyrazol-3-one; Downstream Products: 2-Butynoic acid, syn-(Methyl,methyl)bimane, 2,3,6,7-Tetramethyl-1,5-diazabicyclo[3.3.0]octa-2,6-diene-4,8-dione.
Data compiled from public chemical databases such as PubChem and supplier catalogs; supplier offers are provided by suppliers.
Last updated:
How to cite: Jingsj. "4,4-Dibromo-3-methyl-2-pyrazolin-5-one (CAS 33549-66-5)". Jingsj Chemical Database. https://www.jingsj.com/compound/J-21196-1 (accessed 2026-11-09).
Data for reference only; verify product details with suppliers before purchase.