CAS 137-45-1 1H-Pyrazol-3-ol (HCID 351317)

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Basic information

CAS: 137-45-1
Standard SMILES: O=c1cc[nH][nH]1
InChIKey: XBYRMPXUBGMOJC-UHFFFAOYSA-N
Molecular formula: C3H4N2O
Average molar mass: 84.08 g/mol
Monoisotopic mass: 84.03236276

Names & identifiers

Preferred name: 1H-Pyrazol-3-ol
IUPAC: 1,2-dihydropyrazol-3-one
English name: 3H-PYRAZOL-3-ONE, 1,2-DIHYDRO-
Molecular formula: C3H4N2O
Molecular weight: 84.08

Names & synonyms

1H-Pyrazol-3-ol60456-92-01,2-Dihydro-3H-pyrazol-3-onePyrazol-5-olDTXSID90929655RefChem:438904DTXCID601358399800-331-8878-599-01H-pyrazol-3(2H)-one137-45-11H-Pyrazol-5-ol

Show more names

NSC 520837Pyrazol-3-ol3-Pyrazolone3H-pyrazol-3-one1H-Pyrazol-3-one4-Pyrazolin-3-one

2H-Pyrazol-3-ol1,2-dihydropyrazol-3-one60456-93-15-hydroxypyrazole3-Hydroxypyrazole5-Hydroxy-pyrazolePyrazolinone5-Hydroxy-1H-pyrazole

Database identifiers

CAS: 137-45-1、60456-92-0
PubChem CID: 351317
DTXSID: DTXSID90929655
ChEMBL: CHEMBL4227850
UNII: U35JHQ8347
EC Number: 800-331-8、878-599-0
Nikkaji: J302.253F、J305.313J、J674.247E

Properties

Computed structural properties

XLogP: -0.3
Topological polar surface area: 41.1 Å²
Hydrogen bond donors: 2
Hydrogen bond acceptors: 2
Rotatable bonds: 0
Heavy atoms: 6
Formal charge: 0
Complexity: 97

Physicochemical properties

Melting point: 160 · 160-162 °C
Density: 1.191 · 1.191±0.06 g/cm3(Predicted)
storage temp.: 2 · 2-8°C
pka: 9 · 9.00±0.70(Predicted)
form: solid
color: Pale yellow
InChI: InChI=1S/C3H4N2O/c6-3-1-2-4-5-3/h1-2H,(H2,4,5,6)
InChIKey: XBYRMPXUBGMOJC-UHFFFAOYSA-N
SMILES: N1C=CC(=O)N1
FDA UNII: 35 JHQ8347 · U35JHQ8347
Symbol(GHS): 7 · GHS07
Signal word: Warning
Hazard statements: 302 · H302-H315-H319-H332-H335
Precautionary statements: 261 · P261-P280-P305+P351+P338
HS Code: 2933199090 · 2933199090

Safety & regulation

GHS classification

GHS Classification · 6 items

Warning

H315 (100%): Causes skin irritation [Warning Skin corrosion/irritation]；H319 (100%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]；H335 (100%): May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]

P261, P264, P264+P265, P271, P280, P302+P352, P304+P340, P305+P351+P338, P319, P321, P332+P317, P337+P317, P362+P364, P403+P233, P405, and P501 (click each P-code to see the statement)

The GHS information provided by 1 company from 1 notification to the ECHA C&L Inventory.

Hazard information

Hazard Classes and Categories · 2 items

Skin Irrit. 2 (100%)；Eye Irrit. 2 (100%)；STOT SE 3 (100%)

Skin Irrit. 2 (100%)；Eye Irrit. 2 (100%)

Safety data

hs_code: 2933199090
Signal word: Warning
Symbol(GHS): GHS07
Hazard statements: H302-H315-H319-H332-H335
Precautionary statements: P261-P280-P305+P351+P338

Chemistry & industry

Applications

Uses1,2-Dihydro-3H-pyrazole-3-one, also known as 1H-pyrazole-3(2H)-one, is an organic intermediate that can be prepared by one-step cyclization from methyl propargylate, ethyl acrylate, or (2E)-3-methoxyacrylate.