1,2-Dihydro-3H-pyrazol-3-one
1,2-二氢-3H-吡唑-3-酮
Also known as: 1,2-dihydropyrazol-3-one, 1H-Pyrazol-3(2H)-one, 1H-Pyrazol-5-ol, 1H-pyrazol-3-ol, 3-Pyrazolone, 3H-PYRAZOL-3-ONE, 1,2-DIHYDRO-, 4-Pyrazolin-3-one, NSC 520837, Pyrazol-3-ol, Pyrazol-5-ol
1,2-Dihydro-3H-pyrazol-3-one (CAS 137-45-1) is a compound in the Pharma Intermediates category listed in the Jingsj chemical database. It has the molecular formula C3H4N2O and a molecular weight of 84.077 g/mol. It is also known as 1,2-dihydropyrazol-3-one, 1H-Pyrazol-3(2H)-one and 1H-Pyrazol-5-ol. Key properties include a melting point of 163 °C, a boiling point of 326.1±15.0 °C at 760 mmHg, a density of 1.4±0.1 g/cm3 and a flash point of 151.0±20.4 °C. No supplier offers are currently listed; request a quote. Record last updated Aug 21, 2026.
- CAS No.
- 137-45-1
- Jingsj CID
- J-1307609-6
- Molecular Formula
- C3H4N2O
- Chinese Name
- 1,2-二氢-3H-吡唑-3-酮
- Molecular Weight
- 84.077 g/mol
- Category
- Pharma Intermediates
- Last updated
- 8/21/2026
No offers for this compound yet.
Request a quotePhysicochemical Properties
| Melting Point | 163 °C |
|---|---|
| Boiling Point | 326.1±15.0 °C at 760 mmHg |
| Density | 1.4±0.1 g/cm3 |
| Flash Point | 151.0±20.4 °C |
Frequently Asked Questions
What is the CAS number of 1,2-Dihydro-3H-pyrazol-3-one?
The CAS number of 1,2-Dihydro-3H-pyrazol-3-one is 137-45-1.
What are the molecular formula and molecular weight of 1,2-Dihydro-3H-pyrazol-3-one?
1,2-Dihydro-3H-pyrazol-3-one has molecular formula C3H4N2O and molecular weight 84.077 g/mol.
Data compiled from public chemical databases and supplier catalogs; supplier offers are provided by suppliers.
Last updated:
How to cite: Jingsj. "1,2-Dihydro-3H-pyrazol-3-one (CAS 137-45-1)". Jingsj Chemical Database. https://www.jingsj.com/compound/J-1307609-6 (accessed 2026-10-25).
Data for reference only; verify specifications, grades and regulatory status with suppliers before purchase.