Hazard
Toxic by ingestion and inhalation, irritant
to skin and eyes.
Chemical Properties
white to yellow crystals or crystalline powder
Uses
Chelating agent; in organic synthesis.
Uses
Pyrazole is used in organic synthesis and asa chelating agent.
Uses
Used as a ligand to prepare organometallic compounds.1,2
Definition
A heterocyclic crystalline aromatic compound with a five-membered
ring containing three carbon atoms and
two nitrogen atoms.
Definition
ChEBI: The 1H-tautomer of pyrazole.
Definition
pyrazole: An unsaturated heterocycliccompound having two nitrogenatoms in a five-membered ring,C3H4N2; m.p. 66–70°C; b.p. 168–188°C. Pyrazine is a symmetricdiazine.
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.
Health Hazard
The acute toxic symptoms from oral administrationof pyrazole in experimental animalswere ataxia, muscle weakness, and respiratorydepression. It is less toxic than pyrroleand pyrrolidine. The oral LD50 value in miceis within the range 1450 mg/kg.
Pyrazole exhibited reproductive toxicityin rats and mice when administered by oralor intraperitoneal route. The effects includefetal death, developmental abnormalities pertainingto the urogenital system, and postimplantationmortality.
Fire Hazard
Noncombustible solid.
Flammability and Explosibility
Notclassified
Purification Methods
Crystallise pyrazole from pet ether, cyclohexane, or water. Its solubility in H2O at 9.6o is 2.7moles/L, and at 24.8o it is 19.4moles/L; in cyclohexane at 31.8o it is 0.577moles/L, and at 56.2o it is 5.86moles/L; and in benzene at 5.2o it is 0.31moles/L, and at 46.5o it is 16.8moles/1000mL. [Barszcz et al. J Chem Soc, Dalton Trans 2025 1986, Beilstein 23 H 39, 23 I 15, 23 II 33, 23 III/IV 550, 23/4 V 122.]
