Pyridazine

The IUPAC name of this product is pyridazine. With the CAS registry number 289-80-5, it is also named as 1,2-Diazabenzene; Orthodiazine. The product's categories are heterocycles, organoborons, pyridazine, building blocks, heterocyclic building blocks and pyridazines. In addiotion, it is clear yellowish-brown liquid which is miscible with water.

The other characteristics of this product can be summarized as: (1)ACD/LogP: -0.77; (2)# of Rule of 5 Violations: 0; (3)ACD/LogD (pH 5.5): -0.77; (4)ACD/LogD (pH 7.4): -0.77; (5)ACD/BCF (pH 5.5): 1; (6)ACD/BCF (pH 7.4): 1; (7)ACD/KOC (pH 5.5): 9.07; (8)ACD/KOC (pH 7.4): 9.08; (9)#H bond acceptors: 2; (10)#H bond donors: 0; (11)#Freely Rotating Bonds: 0; (12)Index of Refraction: 1.503; (13)Molar Refractivity: 22.43 cm³; (14)Molar Volume: 75.8 cm³; (15)Polarizability: 8.89×10^-24 cm³; (16)Surface Tension: 44.1 dyne/cm; (17)Enthalpy of Vaporization: 42.61 kJ/mol; (18)Vapour Pressure: 0.315 mmHg at 25°C; (19)Exact Mass: 80.037448; (20)MonoIsotopic Mass: 80.037448; (21)Topological Polar Surface Area: 25.8; (22)Heavy Atom Count: 6; (23)Complexity: 30.5.

Preparation of Pyridazine: It can be obtained by 4,4-diethoxy-3-hydroxy-butyraldehyde with hydrazyne sulfate in the solvent methanol and H₂O at 50 °C. The reaction time is 18 hours. The yield is 80%.

Uses of Pyridazine: It is mainly used in research and industry as building block for more complex compounds. It is also supposed to be used as organic intermediate. For example: It can react with diphenyl-cyclopropenone to get 6,7-diphenyl-pyrrolo[1,2-b]pyridazin-5-ol. This reaction needs solvent 1,2-dichloro-ethane by heating. The reaction time is 2 hours.

When you are using this chemical, please be cautious about it as the following:
It is irritating to eyes, respiratory system and skin, so people should not breathe vapour and avoid contact with skin and eyes.

People can use the following data to convert to the molecule structure. 
1. SMILES: n1ncccc1;
2. InChI: InChI=1/C4H4N2/c1-2-4-6-5-3-1/h1-4H.

The following is the toxicity data which has been tested.

Organism	Test Type	Route	Reported Dose (Normalized Dose)	Effect	Source
mouse	LD50	intraperitoneal	2650mg/kg (2650mg/kg)		Progress in Biochemical Pharmacology. Vol. 1, Pg. 542, 1965.