Malononitrile CAS 109-77-3

Malononitrile, with the CAS number 109-77-3, is an aliphatic dinitrile characterized by its chemical formula C₃H₂N₂. It appears as a white crystalline solid or colorless powder and is known for its high toxicity and potential to release cyanide under certain conditions.
Chemical Properties
Molecular Weight: 66.06 g/mol
Melting Point: Approximately 30.5°C
Boiling Point: Around 220°C
Density: Approximately 1.049 g/cm³ at 20°C
Solubility: Soluble in water and various organic solvents, including alcohols and benzene, but insoluble in non-polar solvents like petroleum ether.
Uses
Malononitrile serves as a crucial building block in organic synthesis, particularly in the production of:
Pharmaceuticals (e.g., triamterene, methotrexate, and vitamin B1)
Pesticides and herbicides
Dyes and synthetic fibers
It is also utilized in the synthesis of various organic compounds due to its reactive cyano groups, which can participate in nucleophilic reactions.
Toxicity and Safety
Malononitrile is highly toxic, with acute toxicity levels greater than those of many aliphatic mononitriles. It can cause severe irritation to the skin and eyes and is toxic if ingested or inhaled. The LD50 values indicate significant toxicity, with values around 19 mg/kg for oral exposure in mice and 28 mg/kg for intravenous exposure in rabbits.
Due to its hazardous nature, it is essential to handle malononitrile with care, using appropriate personal protective equipment and following safety protocols to prevent exposure.
Production Methods
Malononitrile can be synthesized through several methods, including:
Continuous reaction of preheated acetonitrile with cyanogen chloride at high temperatures.
Reaction of phosphorus pentachloride with cyanoacetamide.
Other methods involving the reaction of malonamide with phosphorus pentoxide.
In summary, malononitrile is a versatile and important chemical in various industrial applications, but its handling requires strict safety measures due to its toxic properties.