Pyrazine

Reported in EPA TSCA Inventory.

The Pyrazine, with the CAS registry number 290-37-9, is also known as 1,4-Diazabenzene. It belongs to the product categories of Chloropyrazines; Pyrazines; Alphabetical Listings; Flavors and Fragrances; O-P; Building Blocks; Heterocyclic Building Blocks. Its EINECS registry number is 206-027-6. This chemical's molecular formula is C₄H₄N₂ and molecular weight is 80.09. What's more, its IUPAC name is the same with its product name. Pyrazine is a symmetrical molecule with point group D2h.

Physical properties about Pyrazine are: (1)# of Rule of 5 Violations: 0; (2)ACD/BCF (pH 5.5): 1; (3)ACD/BCF (pH 7.4): 1; (4)ACD/KOC (pH 5.5): 23.756; (5)ACD/KOC (pH 7.4): 23.757; (6)#H bond acceptors: 2; (7)#H bond donors: 0; (8)#Freely Rotating Bonds: 0; (9)Polar Surface Area: 25.78 Å²; (10)Index of Refraction: 1.503; (11)Molar Refractivity: 22.435 cm³; (12)Molar Volume: 75.881 cm³; (13)Surface Tension: 44.125 dyne/cm; (14)Density: 1.055 g/cm³; (15)Flash Point: 55.556 °C; (16)Enthalpy of Vaporization: 34.208 kJ/mol; (17)Boiling Point: 118.634 °C at 760 mmHg; (18)Vapour Pressure: 19.741 mmHg at 25 °C.

Preparation of Pyrazine: this chemical can be prepared by Piperazine. This reaction needs catalyzer Pt-Al₂O₃-In₂O₃-Re at temperature of 400 °C. The yield is 78.7 %.

Uses of Pyrazine: (1) it is used as pharmaceutical intermediates and essence, perfume intermediates; (2) it is used to produce other chemicals. For example, it can produce Pyrazine 1-oxide. The reaction occurs with reagents sodium perborate tetrahydrate, acetic acid at temperature of 80 °C. The yield is 52.8 %.

When you are dealing with this chemical, you should be very careful. It may catch fire in contact with air, only need brief contact with an ignition source and have a very low flash point or evolve highly flammable gases in contact with water. This chemical is irritating to eyes, respiratory system and skin. Therefore, you should keep away from sources of ignition and wear suitable protective clothing. In case of contacting with eyes, you should rinse immediately with plenty of water and seek medical advice.

You can still convert the following datas into molecular structure:
(1) SMILES: c1cnccn1
(2) InChI: InChI=1S/C4H4N2/c1-2-6-4-3-5-1/h1-4H
(3) InChIKey: KYQCOXFCLRTKLS-UHFFFAOYSA-N

The toxicity data is as follows:

Organism	Test Type	Route	Reported Dose (Normalized Dose)	Effect	Source
mouse	LD50	intraperitoneal	2730mg/kg (2730mg/kg)		Progress in Biochemical Pharmacology. Vol. 1, Pg. 542, 1965.