14Diiodobenzene

1,4-Diiodobenzene is an organic compound belonging to the class of aromatic hydrocarbons, specifically a disubstituted benzene derivative where two iodine atoms are attached to the carbon ring at the para (1,4) positions. It is represented by the chemical formula C6H4I2, with a molecular weight of approximately 303.88 g/mol. This compound is a white to off-white crystalline solid that is insoluble in water but soluble in organic solvents such as ethanol, ether, and chloroform.

Synthesis of 1,4-diiodobenzene typically involves the electrophilic aromatic substitution of benzene with iodine, often facilitated by a catalyst such as iodine monochloride (ICl) or iodine monobromide (IBr). Alternatively, it can be prepared through the Sandmeyer reaction starting from *p*-iodoaniline, where the amino group is replaced by iodine. The compound is also commercially available and is used as a precursor in organic synthesis.

1,4-Diiodobenzene serves as a key intermediate in the production of various functionalized aromatic compounds. It can undergo further halogen-lithium exchange reactions to form organolithium reagents, which are useful in cross-coupling reactions such as Suzuki, Stille, or Heck couplings. These reactions enable the synthesis of complex organic molecules, including pharmaceuticals, agrochemicals, and materials science applications.

The compound exhibits moderate stability under normal conditions but can decompose upon exposure to strong oxidizing agents or high temperatures. It is generally handled under controlled laboratory conditions due to its potential reactivity. Safety precautions, such as proper ventilation and the use of protective equipment, are recommended when working with 1,4-diiodobenzene to minimize exposure risks.

In research settings, 1,4-diiodobenzene is often employed in studies involving organic synthesis, materials chemistry, and supramolecular chemistry. Its symmetrical structure and reactivity make it a versatile building block for constructing conjugated systems and other functionalized aromatic frameworks.