Pyrazole

1H-PYRAZOLE · PYRAZOL · 1H-Pyrazol · Pyrrazole · α-yrromonazole · Pyrazole, pure, 98% · PYRAZOLE · Ryrazole

Identifiers & Physical Properties

CAS No.	288-13-1
Molecular formula	C3H4N2
Average molar mass	68.08 g/mol
Monoisotopic mass	68.03744813 g/mol
SMILES	c1cn[nH]c1
InChIKey	WTKZEGDFNFYCGP-UHFFFAOYSA-N
PubChem CID	1048
ChEMBL	CHEMBL15967
ChEBI	CHEBI:17241
EC No.	206-017-1
DTXSID	DTXSID2059774

Chemical & Physical Properties

XLogP	0.3
Topological polar surface area	28.7
Hydrogen bond donors	1
Hydrogen bond acceptors	1
Rotatable bonds	0
Heavy atoms	5
Formal charge	0
Complexity	28.1
Chemical classes	Nitrogen Compounds -> Pyrazoles
Drugs	Pharmaceuticals -> Listed in ZINC15
SpringerMaterials Properties	15N nuclear magnetic resonance spectrum
LogP (partition coefficient)	0.13
Vapor pressure	1.19 [mmHg]21Pa at 20℃
Physical Description	LiquidSolid with an odor like pyridine[Merck Index] Colorless crystalline solid[Sigma-Aldrich MSDS]
Dissociation Constants	2.48 (at 25 °C)
Collision Cross Section	125.47 Å² [M+H]+ [CCS Type: DTMethod: stepped-field]
Melting point	67-70 °C (lit.)
Boiling point	186-188 °C (lit.)
Density	1.4088 (rough estimate)
Refractive index	1.4203
Flash point	186-188°C
Storage conditions	Store below +30°C.
Solubility	Chloroform, MethanolSOLUBLE
Physical state	Crystals or Crystalline Powder
pKa (acidity coefficient)	2.49(at 25℃)
Color	White to yellow
Specific heat capacity	Cp(crystal): 1.19 J/(g·K), at 25℃
Sensitivity	Hygroscopic
Merck	14,7960
BRN	103775
InChI	1S/C3H4N2/c1-2-4-5-3-1/h1-3H,(H,4,5)
InChIKey	WTKZEGDFNFYCGP-UHFFFAOYSA-N
SMILES	c1cn[nH]c1
LogP (partition coefficient)	0.33 at 25℃
CAS DataBase Reference	288-13-1(CAS DataBase Reference)
EWG's Food Scores	1
FDA UNII	3QD5KJZ7ZJ
NIST Chemistry Reference	1H-Pyrazole(288-13-1)
EPA Substance Registry System	Pyrazole (288-13-1)
UNSPSC Code	12352100
NACRES	NA.22
GHS pictogram	GHS05,GHS06,GHS08
Signal word	Danger
GHS hazard statements	H302-H311-H315-H318-H373-H412
GHS precautionary statements	P273-P280-P301+P312-P302+P352+P312-P305+P351+P338-P314
Target organs	spleen,Thyroid
Hazard symbols	Xn
Risk statements (R)	22-36/37/38-52-20/21/22
Safety statements (S)	26-36/37-61-37/39-36
UN transport number	2811
Water hazard class (WGK)	1
RTECS number	UQ4900000
TSCA inventory status	TSCA listed
Hazard class	6.1(b)Acute Tox. 3 DermalAcute Tox. 4 OralAquatic Chronic 3Eye Dam. 1Skin Irrit. 2STOT RE 1
Packing group	III
Customs code	29331990
Storage class	6.1C - Combustible acute toxic Cat.3toxic compounds or compounds which causing chronic effects
Toxicity	LD50 (24 hr) in rats, mice (mmol/kg): 19, 21 i.v.21, 22 orally (Magnussen)
REACH registrations	Active
Limited quantities	5.0 kg (11 lbs) (solid)
Excepted quantities	Max Inner Pack (30g or 30ml) and Max Outer Pack (1Kg or 1L)

Safety & Regulations

GHS classification	This chemical does not meet GHS hazard criteria for 0.4% (1 of 265) of reports.DangerH302 (98.9%): Harmful if swallowed [Warning Acute toxicity, oral]P260, P261, P262, P264, P264+P265, P270, P271, P273, P280, P301+P317, P302+P352, P304+P340, P305+P351+P338, P305+P354+P338, P316, P317, P319, P321, P330, P332+P317, P337+P317, P361+P364, P362+P364, P403+P233, P405, and P501 (click each P-code to see the statement)Aggregated GHS information provided per 265 reports by companies from 21 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.
Regulatory information	Chemical: 1H-Pyrazole1H-Pyrazole is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of 1H-Pyrazole are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)Status: Active Update: 26-02-2019 https://echa.europa.eu/registration-dossier/-/registered-dossier/23403Pyrazole: Does not have an individual approval but may be used under an appropriate group standard
Hazards summary	Equivocal evidence of teratogenicity in miceTeratogenic effects observed in intraperitoneal study of rats (route of administration not relevant to humans)[REPROTOX] Causes zonal hepatitis and coma in oral lethal-dose studies of rats[RTECS] A skin and strong eye irritantHarmful by ingestionTeratogenicity observed in rats[Sigma-Aldrich MSDS]
Hazard Classes and Categories	Acute Tox. 4 (98.9%)
Adverse effects	Occupational hepatotoxin - Secondary hepatotoxins: the potential for toxic effect in the occupational setting is based on cases of poisoning by human ingestion or animal experimentation.
Water hazard class (WGK)	1
TSCA inventory status	TSCA listed
RTECS number	UQ4900000
UN transport number	2811
Customs code	29331990
Toxicity	LD50 (24 hr) in rats, mice (mmol/kg): 19, 21 i.v.21, 22 orally (Magnussen)
Risk statements (R)	22-36/37/38-52-20/21/22
Signal word	Danger
GHS pictogram	GHS05,GHS06,GHS08
Hazard symbols	Xn
Safety statements (S)	26-36/37-61-37/39-36
Hazard class	6.1(b)Acute Tox. 3 DermalAcute Tox. 4 OralAquatic Chronic 3Eye Dam. 1Skin Irrit. 2STOT RE 1
Storage class	6.1C - Combustible acute toxic Cat.3toxic compounds or compounds which causing chronic effects
Packing group	III
Target organs	spleen,Thyroid
GHS hazard statements	H302-H311-H315-H318-H373-H412
Limited quantities	5.0 kg (11 lbs) (solid)
Excepted quantities	Max Inner Pack (30g or 30ml) and Max Outer Pack (1Kg or 1L)
REACH registrations	Active
GHS precautionary statements	P273-P280-P301+P312-P302+P352+P312-P305+P351+P338-P314

Applications & Uses

Uses

Pyrazole is used in organic synthesis and asa chelating agent.

General Description

Pyrazine is a heterocyclic crystalline aromatic compound with a five-membered ring containing three carbon atoms and two nitrogen atoms. It is a symmetricdiazine.