Metadiiodobenzene

Metadiiodobenzene, also known as 1,3-diiodobenzene, is an aromatic organic compound belonging to the class of dihalobenzenes. It consists of a benzene ring with two iodine atoms attached at the meta positions, specifically at the carbon atoms numbered 1 and 3. The chemical has the molecular formula C6H4I2 and a molar mass of approximately 303.9 g/mol.

This compound is typically synthesized through the electrophilic aromatic substitution of benzene with iodine, often using a catalyst such as iodine monochloride (ICl) or iodine in the presence of an oxidizing agent like nitric acid. It can also be prepared via the Sandmeyer reaction from meta-aminobenzoic acid or other meta-substituted aromatic amines.

Metadiiodobenzene is a white to off-white crystalline solid with a relatively low solubility in water but higher solubility in organic solvents such as ethanol, ether, and chloroform. It exhibits typical properties of aromatic compounds, including stability under normal conditions and reactivity in certain organic reactions.

The compound has limited industrial applications but serves as a useful intermediate in organic synthesis. Its meta substitution pattern influences its reactivity, often making it distinct from its ortho- and para-isomers. Research into diiodobenzenes, including metadiiodobenzene, is relevant in fields such as pharmaceutical chemistry, where halogenated aromatic compounds may serve as precursors to biologically active molecules.

Handling metadiiodobenzene requires standard laboratory precautions, as iodine can be irritating to skin and mucous membranes, and its vapors may pose inhalation risks. Proper ventilation and protective equipment are recommended when working with the compound.